[Protective effect of recombinant Schistosoma japonicum cystatin against acute kidney injury associated with acute liver failure in mice]

OBJECTIVE

To evaluate the protective effect of recombinant Schistosoma japonicum cystatin (rSj-Cys) against acute kidney injury induced by acute liver failure and unravel the underlying mechanism, so as to provide insights into the clinical therapy of acute kidney injury.

METHODS

Twenty-four male C57BL/6J mice at ages of 6 to 8 weeks were randomly divided into the normal control group, rSj-Cys control group, lipopolysaccharide (LPS)/D-galactosamine (D-GaIN) model group and LPS/D-GaIN + rSj-Cys treatment group, of 6 mice each group. Mice in the LPS/D-GaIN group and LPS/D-GaIN + rSj-Cys group were intraperitoneally injected with LPS (10 μg/kg) and D-GaIN (700 mg/kg), and mice in the LPS/D-GaIN + rSj-Cys group were additionally administered with rSj-Cys (1.25 mg/kg) by intraperitoneal injection 30 min post-modeling, while mice in the rSj-Cys group were intraperitoneally injected with rSj-Cys (1.25 mg/kg), and mice in the normal control group were injected with the normal volume of PBS. All mice were sacrificed 6 h post-modeling, and mouse serum and kidney samples were collected. Serum creatinine (Cr) and urea nitrogen (BUN) levels were measured, and the pathological changes of mouse kidney specimens were examined using hematoxylin-eosin (HE) staining. Serum tumor necrosis factor (TNF)-α and interleukin (IL)-6 levels were detected using enzyme-linked immunosorbent assay (ELISA), and the expression of inflammatory factors and pyroptosis-related proteins was quantified in mouse kidney specimens using immunohistochemistry. In addition, the expression of pyroptosis-related proteins and nuclear factor-kappa B (NF-κB) signaling pathway-associated proteins was determined in mouse kidney specimens using Western blotting assay.

RESULTS

HE staining showed no remarkable abnormality in the mouse kidney structure in the normal control group and the rSj-Cys control group, and renal tubular injury was found in LPS/D-GaIN group, while the renal tubular injury was alleviated in LPS/D-GaIN+rSj-Cys treatment group. There were significant differences in serum levels of Cr (F = 46.33, P < 0.001), BUN (F = 128.60, P < 0.001), TNF-α (F = 102.00, P < 0.001) and IL-6 (F = 202.10, P < 0.001) among the four groups, and lower serum Cr [(85.35 ± 32.05) μmol/L], BUN [(11.90 ± 2.76) mmol/L], TNF-α [(158.27 ± 15.83) pg/mL] and IL-6 levels [(56.72 ± 4.37) pg/mL] were detected in the in LPS/D-GaIN + rSj-Cys group than in the LPS/D-GaIN group (all P values < 0.01). Immunohistochemical staining detected significant differences in TNF-α (F = 24.16, P < 0.001) and IL-10 (F = 15.07, P < 0.01) expression among the four groups, and lower TNF-α [(106.50 ± 16.57)%] and higher IL-10 expression [(91.83 ± 5.23)%] was detected in the LPS/D-GaIN + rSj-Cys group than in the LPS/D-GaIN group (both P values < 0.01). Western blotting and immunohistochemistry detected significant differences in the protein expression of pyroptosis-related proteins NOD-like receptor thermal protein domain associated protein 3 (NLRP3) (F = 24.57 and 30.72, both P values < 0.001), IL-1β (F = 19.24 and 22.59, both P values < 0.001) and IL-18 (F = 16.60 and 19.30, both P values < 0.001) in kidney samples among the four groups, and lower NLRP3, IL-1β and IL-18 expression was quantified in the LPS/D-GaIN + rSj-Cys treatment group than in the LPS/D-GaIN group (P values < 0.05). In addition, there were significant differences in the protein expression of NF-κB signaling pathway-associated proteins p-NF-κB p-P65/NF-κB p65 (F = 71.88, P < 0.001), Toll-like receptor (TLR)-4 (F = 45.49, P < 0.001) and p-IκB/IκB (F = 60.87, P < 0.001) in mouse kidney samples among the four groups, and lower expression of three NF-κB signaling pathway-associated proteins was determined in the LPS/D-GaIN + rSj-Cys treatment group than in the LPS/D-GaIN group (all P values < 0.01).

CONCLUSIONS

rSj-Cys may present a protective effect against acute kidney injury caused by acute liver failure through inhibiting inflammation and pyroptosis and downregulating the NF-κB signaling pathway.

[Efficacy of Barbed reposition pharyngoplasty combined with Han-Uvulopalatopharyngoplasty for the treatment of OSAHS patients]

Objective: To study the efficacy of Barbed reposition pharyngoplasty (BRP) combined with Han-Uvulopalatopharyngoplasty (H-UPPP) in surgical treatment of OSAHS patients. Methods: OSAHS patients admitted to our department from June 2021 to February 2022 who met the surgical enrollment criteria were divided into two groups by surgical procedure: H-UPPP operation group [Control group, 47 cases, including 42 males and 5 females, aged 18-64 (37.77±11.65)years, and H-UPPP+BRP group [Study group, 48 cases, including 45 males and 3 females, aged 23-60 (39.10±9.86) years]. The surgical efficacy 6 months after operation was retrospectively analyzed. Meanwhile, the relationship between the surgical efficacy and modified Friedman pharyngeal anatomical stages was analyzed. The postoperative pain VAS score at first 3 days and the incidence of foreign body sensation in pharynx after 6 months of operation were compared between the two groups. Statistical analysis was conducted by SPSS 23.0. Results: There were no significant differences in gender, age, BMI, Friedman pharyngeal anatomical stages, ESS score, AHI and LSpO2 between the two groups, preoperatively (P>0.05). There was significant difference between the two groups in ratio of cumulative time of oxygen saturation below 90% to total sleep time(CT90), preoperatively. Surgical efficacy of H-UPPP operation group was 48.9% (23/47), while H-UPPP+BRP operation group was 70.8% (34/48), which was statistically significant (χ2=4.74, P=0.029). H-UPPP+BRP group seemed to have a higher surgical efficacy than H-UPPP group in patients with Friedman Ⅱb (87% vs. 61.9%) and Ⅲ stage (44.4% vs. 15%), but there was no statistically significant difference (P>0.05). H-UPPP+BRP group had a higher pain VAS score in first three days (t=-3.10, P=0.003), also had higher incidence of pharyngeal foreign body sensation after 6 months of operation (χ2=4.727, P=0.030). Conclusions: In the surgical treatment of OSAHS patients, the overall efficacy of BRP combined H-UPPP surgery is higher than that of H-UPPP surgery alone. It may be more suitable for OSAHS patients with modified Friedman type Ⅱb and type Ⅲ stage.

[Application of preoperative serum CYFRA 21-1 level in the prognosis of colorectal cancer]

To explore the predictive value of preoperative serum CYFRA 21-1 in colorectal cancer (CRC) resection patients. In this retrospective study, 456 patients with CRC who received surgical treatment in the Department of General Surgery, Affiliated Hospital of Nantong University from January 2016 to February 2018 were analyzed. Preoperative CYFRA 21-1, CEA, CA19-9 and pathological data of the study subjects were collected. Determine the cut-off value of CYFRA 21-1 based on the X-tile. Chi-square test or Fisher exact probability test were used to compare clinicopathological features in different CYFRA 21-1 level groups. Univariate and multivariate regression analysis of factors affecting 5-year overall survival (OS) and disease-free survival (DFS). Kaplan-Meier survival curves were used to analyze 5-year differences in OS and DFS in CRC patients with different levels of CYFRA 21-1, CEA and CA19-9. Receiver operating characteristic(ROC) was adopted. ROC curves were used to analyze the prognostic efficacy of CYFRA21-1 for CRC, and nomogram maps were used to predict 1, 3, and 5-year survival rates. The results showed that the optimal cut-off values of serum CYFRA 21-1, CEA and CA19-9 were 4.9 ng/ml, 29.2 ng/ml and 72.8 U/ml, respectively. Different gender, tumor size, location, degree of differentiation, depth of invasion, lymph node metastasis and tumor node metastasis (TNM) classification stage were significantly different between the two groups with high and low CYFRA 21-1, the P-values were 0.018,<0.001,<0.001,<0.001, 0.002, 0.001, 0.003, respectively. CYFRA 21-1 (≥4.9 ng/ml) was an independent risk factor for 5-year OS (HR: 4.008, 95%CI: 2.309-6.958, P<0.001) and DFS (HR: 3.75, 95%CI: 2.227-6.314, P<0.001) in CRC patients. CYFRA 21-1 predicts a 5-year AUC of 0.725 and 0.720 for OS and DFS, respectively, and 0.804 and 0.827 for the combination of CEA and CA19-9. Based on the results of multivariate Cox regression analysis, nomogram graphs of OS and DFS were established, the C-indexes were 0.799 and 0.803, respectively. In conclusion, preoperative serum CYFRA 21-1 level may be an independent risk factor affecting the prognosis of patients with colorectal cancer. The prognostic model established by CYFRA 21-1 combined with CEA, CA19-9 and TNM stages may provide references for the prevention of CRC recurrence and clinical decision-making.

First Experimental Study of the Purely Leptonic Decay D_{s}^{*+}→e^{+}ν_{e}

Using 7.33  fb^{-1} of e^{+}e^{-} collision data taken with the BESIII detector at the BEPCII collider, we report the first experimental study of the purely leptonic decay D_{s}^{*+}→e^{+}ν_{e}. Our data contain a signal of this decay with a statistical significance of 2.9σ. The branching fraction of D_{s}^{*+}→e^{+}ν_{e} is measured to be (2.1_{-0.9_{stat}}^{+1.2}±0.2_{syst})×10^{-5}, corresponding to an upper limit of 4.0×10^{-5} at the 90% confidence level. Taking the total width of the D_{s}^{*+} [(0.070±0.028)  keV] predicted with the radiative D_{s}^{*+} decay from the lattice QCD calculation as input, the decay constant of the D_{s}^{*+} is determined to be f_{D_{s}^{*+}}=(214_{-46_{stat}}^{+61}±44_{syst})  MeV, corresponding to an upper limit of 354 MeV at the 90% confidence level.

[Analysis on the secondary attack rates of SARS-CoV-2 Omicron variant and the associated factors]

Objective: To evaluate the secondary attack rates of the SARS-CoV-2 Omicron variant and the associated factors. Methods: A total of 328 primary cases and 40 146 close contacts of the SARS-CoV-2 Omicron variant routinely detected in local areas of Jiangsu Province from February to April 2022 were selected in this study, and those with positive nucleic acid test results during 7 days of centralized isolation medical observation were defined as secondary cases. The demographic information and clinical characteristics were collected, and the secondary attack rate (SAR) and the associated factors were analyzed by using a multivariate logistic regression model. Results: A total of 1 285 secondary cases of close contacts were reported from 328 primary cases, with a SAR of 3.2% (95%CI: 3.0%-3.4%). Among the 328 primary cases, males accounted for 61.9% (203 cases), with the median age (Q1, Q3) of 38.5 (27, 51) years old. Among the 1 285 secondary cases, males accounted for 59.1% (759 cases), with the median age (Q1, Q3) of 34 (17, 52) years old. The multivariate logistic regression model showed that the higher SAR was observed in the primary male cases (OR=1.632, 95%CI: 1.418-1.877), younger than 20 years old (OR=1.766, 95%CI: 1.506-2.072),≥60 years old (OR=1.869, 95%CI: 1.476-2.365), infected with the BA.2 strain branch (OR=2.906, 95%CI: 2.388-3.537), the confirmed common cases (OR=2.572, 95%CI: 2.036-3.249), and confirmed mild cases (OR=1.717, 95%CI: 1.486-1.985). Meanwhile, the higher SAR was observed in the close contacts younger than 20 years old (OR=2.604, 95%CI: 2.250-3.015),≥60 years old (OR=1.287, 95%CI: 1.052-1.573) and exposure for co-residence (OR=27.854, 95%CI: 23.470-33.057). Conclusion: The sex and age of the primary case of the Omicron variant, the branch of the infected strain, case severity of the primary case, as well as the age and contact mode of close contacts are the associated factors of SAR.

[Clinical features and prognosis of core binding factor acute myeloid leukemia children in South China: a multicenter study]

Objective: To analyze the clinical features, efficacy and prognosis factors of core binding factor (CBF) acute myeloid leukemia (AML) children in South China. Methods: This was a retrospective cohort study. Clinical data of 584 AML patients from 9 hospitals between January 2015 to December 2020 was collected. According to fusion gene results, all patients were divided into two groups: CBF-AML group (189 cases) and non-CBF-AML group (395 cases). CBF-AML group were divided into AML1-ETO subgroup (154 cases) and CBFβ-MYH11 subgroup (35 cases). Patients in CBF-AML group chosen different induction scheme were divided into group A (fludarabine, cytarabine, granulocyte colony stimulating factor and idarubicin (FLAG-IDA) scheme, 134 cases) and group B (daunorubicin, cytarabine and etoposide (DAE) scheme, 55 cases). Age, gender, response rate, recurrence rate, mortality, molecular genetic characteristics and other clinical data were compared between groups. Kaplan-Meier method was used for survival analysis and survival curve was drawn. Cox regression model was used to analyze prognostic factors. Results: A total of 584 AML children were diagnosed, including 346 males and 238 females. And a total of 189 children with CBF-AML were included, including 117 males and 72 females. The age of diagnosis was 7.3 (4.5,10.0)years, and the white blood cell count at initial diagnosis was 21.4 (9.7, 47.7)×109/L.The complete remission rate of the first course (CR1) of induction therapy, relapse rate, and mortality of children with CBF-AML were significantly different from those in the non-CBF-AML group (91.0% (172/189) vs. 78.0% (308/395); 10.1% (19/189) vs. 18.7% (74/395); 13.2% (25/189) vs. 25.6% (101/395), all P<0.05). In children with CBF-AML, the CBFβ-MYH11 subgroup had higher initial white blood cells and lower proportion of extramedullary invasion than the AML1-ETO subgroup, with statistical significance (65.7% (23/35) vs. 14.9% (23/154), 2.9% (1/35) vs. 16.9% (26/154), both P<0.05). AML1-ETO subgroup had more additional chromosome abnormalities (75/154), especially sex chromosome loss (53/154). Compared with group B, group A had more additional chromosome abnormalities and a higher proportion of tumor reduction regimen, with statistical significance (50.0% (67/134) vs. 29.1% (16/55), 34.3% (46/134) vs. 18.2% (10/55), both P<0.05). Significant differences were found in 5-years event free survival (EFS) rate and 5-year overall survival (OS) rate between CBF-AML group and non-CBF-AML group ((77.0±6.4)%vs. (61.9±6.7)%,(83.7±9.0)%vs. (67.3±7.2)%, both P<0.05).EFS and OS rates of AML1-ETO subgroup and CBFβ-MYH11 subgroup in children with CBF-AML were not significantly different (both P>0.05). Multivariate analysis showed in the AML1-ETO subgroup, CR1 rate and high white blood cell count (≥50×109/L) were independent risk factors for EFS (HR=0.24, 95%CI 0.07-0.85,HR=1.01, 95%CI 1.00-1.02, both P<0.05) and OS (HR=0.24, 95%CI 0.06-0.87; HR=1.01, 95%CI 1.00-1.02; both P<0.05). Conclusions: In CBF-AML, AML1-ETO is more common which has a higher extramedullary involvement and additional chromosome abnormalities, especially sex chromosome loss. The prognosis of AML1-ETO was similar to that of CBFβ-MYH11. The selection of induction regimen group FLAG-IDA for high white blood cell count and additional chromosome abnormality can improve the prognosis.

Listeriolysin O Drives Innate and Adaptive Immune Responses to CD47 Immunotherapy

PURPOSE/OBJECTIVE(S)

Radioimmunotherapies that combine radiation with antibodies against the "don't eat me" signal CD47 show increasing promise. One opportunity to synergize RT with anti-CD47 is via the Stimulator of Interferon Genes (STING) pathway which facilitates potent immune responses to cytoplasmic DNA. Anti-CD47 should activate STING by increasing macrophage consumption of tumor DNA. However, tumor contents are destroyed in phagolysosomes. Listeria (L.) monocytogenes escape lysosomes by secreting a pore-forming protein Listeriolysin O (LLO). We recently engineered a protein-antibody conjugate linking anti-CD47 to LLO. Here, we demonstrate that LLO-CD47 enhances macrophage STING signaling, tumor cell phagocytosis, and tumor antigen presentation. At doses compatible with minimal toxicity in mice, LLO-CD47 delays the growth of orthotopic breast tumors. By contrast, anti-CD47 fails to activate STING in macrophages or inhibit tumor growth. We further hypothesize that LLO-CD47 requires innate and adaptive immune cells for antitumor immunity.

MATERIALS/METHODS

Anti-CD47 was conjugated to LLO using a water-soluble SPDP crosslinker and purified by affinity chromatography. Transmission electron microscopy (TEM) was used to visualize the integrity of macrophage phagolysosomes following treatment. C57B6 mouse bone marrow-derived macrophages (BMDMs) were used to study the impact of LLO-CD47 on M2-to-M1 polarization, tumor cell phagocytosis, STING activation, and antigen presentation. CD8+ T cells or tumor-associated macrophages (TAMs) were depleted from tumor-bearing mice using an anti-CD8 antibody or anti-CSF-1R antibody prior to LLO-CD47 treatment.

RESULTS

(1) LLO-CD47 skews BMDMs from M2-to-M1 inflammatory phenotypes and enhances the phagocytosis of E0771 tumor cells. (2) BMDMs visualized by TEM show breaches in phagosome membranes following LLO-CD47, but not anti-CD47, treatment. (3) LLO-CD47 increases levels of phosphorylated STING, IFN, and TNFα relative to cells treated with anti-CD47. (4) LLO-CD47 significantly inhibits the growth of orthotopically implanted E0771 murine breast tumors relative to anti-CD47. (5) The elimination of CD8+ T cells or TAMs abrogates the antitumor effect of LLO-CD47.

CONCLUSION

LLO-CD47 is a de novo protein-antibody conjugate engineered for cGAS-STING pathway activation in innate immune cells. CD8+ T cells and TAMs are required for the antitumor activity LLO-CD47 in orthotopic models of breast cancer. This novel immunotherapy builds on clinical interest in myeloid checkpoint inhibitors and may be studied as a supplemental therapy for patients with metastatic breast cancer.

Induction Chemotherapy and Toripalimab for Larynx Preservation in Resectable Locally Advanced Laryngeal/Hypopharyngeal Carcinoma: Preliminary Results of INSIGHT Study

PURPOSE/OBJECTIVE(S)

Previous studies have demonstrated excellent pathological response of induction PD-1 inhibitor with chemotherapy for locally advanced head and neck cancer. To our knowledge, there is scarce evidence on induction chemotherapy (ICT) and PD-1 inhibitor in organ preservation for patients (pts) with laryngeal/hypopharyngeal carcinoma. Hence, the aim of this study is to evaluate the efficacy and toxicities of ICT and PD-1inhibitor (Toripalimab) followed by radiotherapy or surgery, for pts with resectable locally advanced laryngeal/hypopharyngeal carcinoma.

MATERIALS/METHODS

This isa single-arm phase II study. Pts with histopathologic confirmed, resectable locally advanced laryngeal/hypopharyngeal squamous cell carcinoma and ECOG PS 0-1 were eligible. Three cycles of ICT (paclitaxel 175 mg/m d1, cisplatin 25 mg/m d1-3) combined with PD-1 inhibitor (Toripalimab 240 mg d0) were given. Response assessment (RECIST 1.1) was performed post-ICT. Patients with complete response (CR)/partial response (PR) of primary tumor received concurrent chemoradiation, followed by maintenance therapy of Toripalimab for eight cycles. Otherwise, patients were referred to surgery, followed by adjuvant radiation (RT)/chemoradiation (CRT), and then maintenance therapy of Toripalimab. The primary endpoint is larynx-preservation (LP) rate at 3 months post-RT. Forty-two patients were planned. Based on a two-stage Fleming design (one-sided α:10%, power: 80%), if at least 22 patients attained LP of the first 27 patients in stage I or at least thirty-two pts attained LP of the 42 patients at the end of stage II, the null hypothesis would be rejected. The cohort would enroll 15 more pts in stage II if 19-21 pts in stage I observed LP, and the study would be terminated if the number of pts with LP were less than 18 in stage I.

RESULTS

A total of 27 pts were enrolled. By the cut-off date Feb 8, 2023, all reached at least 3 months of follow-up post-RT. Median age was 63 (53-74) years with 92.6% male. Hypopharyngeal cancer accounted for 66.7%. There were 74.1% who were T3 to T4, and 77.7% were N2 to N3. Six cases had primary invasion of esophagus and five pts underwent pretreatment tracheostomy. ORR of ICT was 85.2%. Afterward, 21 pts were treated with concurrent CRT, while 6 pts received surgery of primary tumor. At 3 months post-RT, 23 pts attained organ preservation and the LP rate was 85.2%. With a median follow-up of 13.5 months, 1-year OS rate, PFS rate and LP survival rate was 83.1%, 79.5% and 79.4%, respectively. During ICT, 22.2% of pts experienced grade 3-4 treatment-related AEs (TRAEs). The most common grade 3-4 TRAEs were nausea and neutrophil count decreased.

CONCLUSION

The primary endpoint LP rate was met. In this cohort of extensive locally advanced laryngeal/hypopharyngeal carcinoma, ICT and Toripalimab followed by radiotherapy or surgery resulted in satisfactory short-term LP rate and encouraging survival.

Endoscopic Ultrasonography-Derived Maximum Tumor Thickness and Tumor Shrinkage Rate as Independent Prognostic Factors in Locally Advanced Esophageal Squamous Cell Carcinoma after Neoadjuvant Chemoradiotherapy

PURPOSE/OBJECTIVE(S)

Neoadjuvant chemoradiotherapy (NCRT) is increasingly used in patients with locally advanced esophageal squamous cell carcinoma (LA-ESCC). Endoscopic ultrasonography (EUS)-derived maximum tumor thickness (MTT) before and after standard NCRT for LA-ESCC indicates treatment response. However, the accuracy of predicting long-term survival remains uncertain. This study aimed to investigate the association between EUS-derived MTT pre- and post-NCRT and tumor shrinkage rate as well as long-term survival in patients with LA-ESCC receiving NCRT.

MATERIALS/METHODS

We retrospectively enrolled patients with LA-ESCC who underwent EUS examination pre- and post-NCRT from 2017 to 2021. MTT was measured using EUS. Tumor shrinkage rate was the ratio of the difference between pre- and post-MTT to pre-MTT. The most fitted cut-off value defining the EUS response was determined by the receiver operating characteristic curve. Univariate and multivariate Cox regression analyses and Kaplan-Meier (KM) curves were used to calculate overall survival (OS) and progression-free survival (PFS). Data from another center were also used for external validation testing.

RESULTS

The median follow-up period was 30.6 months.230 patients with LA-ESCC who underwent EUS pre- or post-NCRT were enrolled. Of the patients, 178 completed the first EUS pre-NCRT and obtained pre-MTT, 200 completed the re-examined EUS post-NCRT and obtained post-MTT, and 148 completed both EUS and achieved tumor shrinkage. In the whole group the 1-year and 3-year OS rates were 93.9% and 67.9%, and PFS rates were 77.7% and 54.1%, respectively. Thinner post-MTT (≤8.8 mm) and EUS-responders (tumor shrinkage rate≥52%) were independently associated with better OS. The result of EUS-respond was an independent prognostic factor could be confirmed in the external validation group. Among LA-ESCC patients with initial ultrasonic T2-3 staging and T4 staging, no statistically differences were observed between the responder and non-responder groups (P = 0.082; P = 0.190).

CONCLUSION

EUS-derived MTT and tumor shrinkage post-NCRT are independent prognostic factors for long-term survival and may be an alternative method for evaluating tumor response in patients with LA-ESCC after NCRT. Initial tumor infiltration beyond esophageal adventitial layer on ultrasound effect could not, however, predict the long-term prognosis.

Comparison of Pathologic Response and Survival Outcomes between Neoadjuvant Immunochemotherapy (nICT) and Neoadjuvant Chemoradiotherapy (nCRT) in Patients with Locally Advanced Esophageal Squamous Cell Carcinoma: A Propensity Score-Matched Analysis

PURPOSE/OBJECTIVE(S)

The neoadjuvant immunochemotherapy (nICT) is a novel treatment, which is likely to be safer for locally advanced, surgically resectable Esophageal squamous cell carcinoma (ESCC) that comparing with the traditional neoadjuvant therapy. However, the efficacy of nICT was controversial and the survival benefit remain unknown.

MATERIALS/METHODS

This study included 313 patients with locally advanced ESCC who underwent surgery following neoadjuvant therapy at Sichuan Cancer Hospital from June 2017 and September 2021. The patients were divided into nICT group and neoadjuvant chemoradiotherapy (nCRT) group according to the neoadjuvant strategy. A 1:2 propensity score matching (PSM) was used to balance potential bias across several covariates between two groups with a caliper 0.05.

RESULTS

Among the 146 patients after PSM, the baseline factors were comparable between two groups. Compared with the nCRT group, the nICT group shown a lower pathologic complete response(pCR) rate (11.54% vs 35.11%; P = 0.0039) and lymph nodes uninvolved rate (ypN0: 44.23% vs 62.77%; P = 0.0154), but a higher perineural invasion (32.69% vs 12.77%; P = 0.0075) and angioinvasion rate (40.38% vs 10.64%; P = 0.0001). However, the 2-year OS and DFS rates were similar between the nICT group and the nCRT group in overall study cohort, and these data were confirmed in the matched samples (2-year OS, 78.2% vs 77.2% [p = 0.95]; DFS, 56.9% vs 58.0% [p = 0.69]).

CONCLUSION

Our preliminary findings indicate that, for individuals with locally advanced ESCC, nICT followed by surgery appears to be less effective in pathologic outcomes, while having a comparable survival rate to nRCT. These results imply a complicated and possibly multifaceted link between the kind of neoadjuvant therapy, the pathologic outcomes, and the final survival.

Dosimetric Predictors of Acute Diarrhea in Locally Advanced Rectal Cancer Patients Treated with Neoadjuvant Chemoradiation with Capecitabine and Irinotecan: A Discovery and Validation Study

PURPOSE/OBJECTIVE(S)

Additional irinotecan can increase the pCR rate from 15% to 30% compared with capecitabine-based neoadjuvant chemoradiotherapy in locally advanced rectal cancer, while more acute diarrhea was induced and predictors of diarrhea have yet to be fully elucidated. In this analysis, we report the incidence of and factors associated with grade 3+ acute diarrhea in LARC patients treated with the CaplriRT regimen in the CinClare trial.

MATERIALS/METHODS

We identified the dosimetric markers with a lasso-Cox risk scoring model tested on CaplriRT group patients in the CinClare trial at our institution from 2015 to 2017 (CinClare, NCT02605265), and then independently validated according to a predefined protocol in patients treated with neoadjuvant chemoradiation with capecitabine and irinotecan from 2019 to 2022 (NCT05688033). Clinical documentation and patient-reported outcomes were reviewed to determine grade 3+ acute diarrhea events.

RESULTS

A total of 116 patients from Cinclare trial treated with CaplriRT regimen were used as a training cohort to obtain dosimetric prediction model and 168 patients were used for independent validation. The majority received 50 Gray (Gy) in 25 fractions with concurrent capecitabine and irinotecan. Median number of concurrent chemotherapy cycles received was 4 (IQR: 3-4). Seventeen (23.6%) patients treated with the CaplriRT regimen in the CinClare trial experienced grade 3+ acute diarrhea. Dosimetric predictors of acute diarrhea included peritoneal space volume receiving 25 Gy or greater (V25Gy). The single multivariate Cox regression, and receiver operating characteristic (ROC) curve analysis showed that the model had good predictive ability (p<0.05). It was also validated using the validation cohort. Patients with peritoneal space V25Gy>950 cm3 were associated with a higher risk of 3+ acute diarrhea compared with those without constraints of V25Gy (p = 0.002).

CONCLUSION

Peritoneal space V25Gy as an important predictor of acute diarrhea during capecitabine and irinotecan neoadjuvant chemoradiation treatment. Peritoneal space V25Gy < 950 cm3 may reduce acute diarrhea toxicity.

Genomic Signature for Oligometastatic Disease in Non-Small Cell Lung Cancer Patients with Brain Metastases

PURPOSE/OBJECTIVE(S)

Biomarkers for oligometastatic disease remain elusive and few studies have attempted to correlate genomic data to the presence of true oligometastatic disease.

MATERIALS/METHODS

Patients with non-small cell lung cancer (NSCLC) and brain metastases were identified in our departmental database. Electronic medical records were used to identify patients for whom liquid biopsy-based comprehensive genomic profiling (Guardant Health) was available. Oligometastatic disease was defined as patients having ≤5 non-brain metastases without diffuse involvement of a single organ. Widespread disease was any spread beyond oligometastatic. Fisher's exact tests were used to identify mutations statistically associated (p<0.1) with either oligometastatic or widespread extracranial disease. A score of +1 was assigned for every mutation present associated with oligometastatic disease, and -1 was assigned for mutations associated with widespread disease. Scores were summed for each patient to create a risk score for the likelihood of oligometastatic disease, with scores subsequently correlated to the likelihood of having oligometastatic disease vs widespread disease. For oligometastatic patients, a competing risk analysis was done to assess for cumulative incidence of oligometastatic progression accounting for the potential competing risks of widespread progression of extracranial disease or death. Cox regression was used to determine the association between oligometastatic risk score and oligometastatic progression.

RESULTS

One hundred thirty patients met study criteria and were included in the analysis. 51 patients (39%) had oligometastatic disease. Genetic mutations included in the Guardant panel associated (p<0.1) with the presence of oligometastatic extracranial disease included ATM, JAK2, MAP2K2, and NTRK1; ARID1A and CCNE1 were associated with widespread disease. Patients with a positive, neutral and negative risk score for oligometastatic disease had a 78%, 41% and 11.5% likelihood of having oligometastatic disease, respectively (p<0.0001). Overall survival for patients with positive, neutral and negative risk scores for oligometastatic disease was 86% vs 82% vs 64% at 6 months (p = 0.2). The competing risk analysis found that the oligometastatic risk score was significantly associated with the likelihood of oligometastatic progression based on the Wald Chi-square test. Patients with positive, neutral and negative risk scores for oligometastatic disease had a cumulative incidence of oligometastatic progression of 77% vs 35% vs 33% at 6 months (p = 0.03 from competing risk model).

CONCLUSION

Elucidation of a genomic signature for oligometastatic disease derived from non-invasive liquid biopsy appears feasible for NSCLC patients. Patients with the oligometastatic signature exhibited higher rates of early oligometastatic progression. Validation of this signature could lead to a biomarker that has the potential to direct local therapies in oligometastatic patients.

The Potential Ability of Plan Complexity Metrics on the Dose Calculation and Plans Delivery in Intensity Modulated Radiotherapy

PURPOSE/OBJECTIVE(S)

The excessive modulation of treatment plan during radiotherapy (RT) increases the complexity. Evaluation of the multidimensional relationship between program complexity metrics, computation-based patient-specific quality assurance (PSQA), and conventional measurement-based PSQA could assist in enhancing the robustness of treatment planning, guide the allocation of clinical QA resources, and ultimately lessen QA workload.

MATERIALS/METHODS

The fifty-five metrics affecting RT planning and delivery accuracy were calculated by a house-built program to describe the complexity of 404 dynamic IMRT plans, with sensitivity to the small field, aperture position, MLC edge, low MUs, MLC leaf motion, leaf speed/acceleration, etc. The calculation-based PSQA was performed using Monte Carlo (MC) method and Collapsed Cone Convolution (CCC) algorithm, implemented in SciMoCa and Mobius 3D, respectively. The measurement-based PSQA was performed using 3D diode arrays with different geometries covering "O", "+" and " × " shapes which exist in ArcCheck, Delta4 phantom+ (Delta4) and Delta4PT phantom (Delta4PT), respectively. Gamma passing rates (GPRs) were recorded to measure the results of each QA system. This multidimensional relationship was evaluated using correlation analysis and principal component linear regression (PCR) analysis.

RESULTS

A total of 4448 GPRs for various QA systems corresponding to two Linacs were counted. The modulation index for speed (MIs) and modulation index for acceleration (MIa) were consistently located at the high points of the radarplots of the Spearman correlation coefficient |rs| between metrics and GPRs of the four QA systems, just except Delta4. Besides, the rs between SciMoCa and ArcCheck were 0.275-0.531 (P ≤ 0.001), SciMoCa and Delta4 were 0.32-0.418 (P ≤ 0.001), and Mobius 3Dand Delta4PT were 0.124-0.226 (P ≤ 0.05). The PCR model's coefficients determination (R2) for SciMoCa were 0.461-0.756 (P ≤ 0.001), ArcCheck were 0.243-0.440 (P ≤ 0.001), Delta4 were 0.268-0.402 (P ≤ 0.001), Mobius 3D were 0.299-0.407 (P ≤ 0.001), and Delta4PT were 0.087-0.141 (P ≤ 0.05).

CONCLUSION

This study is the first overall assessment of the impact of various complexity metrics on the accuracy of TPS calculation and Linac delivery. Of the metrics studied, MIs and MIa metrics have a standout impact on the ability of the TPS calculation and delivery system, extra attention should be paid during the planning process. It is inappropriate to utilize calculation-based QA to predict the results of measurement-based QA since there is a poor correlation between the two. Furthermore, calculation-based QA outperforms measurement-based QA in identifying highly complex plans, which can further guide clinical QA process optimization and save limited clinical resources.

Using Longitudinal MRI to Manage Proton Range Uncertainty for Pediatric Proton Craniospinal Irradiation

PURPOSE/OBJECTIVE(S)

Clinical evidence has shown that proton therapy can effectively reduce side effects for pediatric patients undergoing vertebral body-sparing craniospinal irradiation (VBS CSI), compared to conventional photon treatment modalities. However, radiation-induced growth impairment remains challenging for VBS CSI due to proton range uncertainty, compromising vertebral body sparing for growing children. Previous studies have shown that fatty marrow replacement can be observed in vertebral bodies 4-48 weeks after treatment is complete. This study aims to detect and quantify the fatty marrow replacement in vertebral bodies using longitudinal magnetic resonance (MR) to manage proton range uncertainty.

MATERIALS/METHODS

A prospective clinical trial of proton VBS CSI was designed, and ten pediatric patients were enrolled with prescribed doses of 15-36 Gy. The thecal sac and neural foramina were the clinical target volumes, and a Monte Carlo planning system was used to robustly optimize treatment plans with a 3.5% range margin. We analyzed patients' T1/T2 MR images acquired before, during, and after proton treatment to investigate the hematopoietic marrow transformation induced by irradiation. A metric was defined to calculate the ratio of fatty and hematopoietic marrow based on relative MR intensity histograms. We proposed a machine learning method via Gaussian fitting process (ML-GFP) to explore hidden correlations between marrow transition and radiation dose to 2 cm3 of the bone marrow (D2cc). We also leveraged this method to embed uncertainty to support potential proton range management for VBS enhancement.

RESULTS

The results indicated that fatty marrow replacement could be observed during inter-fractional treatment. For instance, an individual patient showed that the fatty marrow generation ratios were 0.54, 0.74, and 0.45, corresponding to 11, 18, and 65 days after the treatment started. Using ML-GFP, the fatty marrow transition was found to be quadratically correlated to treatment fractions, and the maximum transformation ranged from 40 to 50 days. Then marrow regeneration was observed due to the decrease in fatty marrow ratios. The fatty marrow ratios were also positively correlated to the D2cc doses ranging from 10 Gy to 36 Gy. Limited by insufficient low-dose data, the ML-GFP model extrapolated the data to predict the marrow transformation below 10 Gy.

CONCLUSION

We demonstrated the feasibility of using non-invasive longitudinal MR to quantify the fatty marrow transition from inter-fractional treatment. Based on this prospective study, the method can detect early fatty marrow generation in vertebrae caused by proton irradiation due to the conservative range margin used for robust optimization. The proposed method could be used to validate the actual proton range, allowing an accurate range margin to be defined to preserve bone marrow. Future investigation will likely focus on clinical implementation to improve life quality for pediatric CSI patients.

A Phase 2 Trial of Efficacy and Safety of Intraoperative Radiation Therapy for Locally Advanced Laryngocarcinoma

PURPOSE/OBJECTIVE(S)

For locally advanced laryngeal cancer (LAL), the local recurrence rate remains 19-40% after radical surgery with postoperative radiotherapy alone or with concurrent chemoradiotherapy in patients with unfavorable prognostic factors. We evaluate local control and acute toxicity of intraoperative radiation therapy (IORT) as a tumor bed boost for locally advanced laryngeal cancer in this prospective phase 2 trial.

MATERIALS/METHODS

This phase II clinical study in which a total of 63 LAL patients (T2N1-3/T3N0-3/T4N0-3) were selected and received IORT (T2: 8-10Gy, T3,4:12-15 Gy) as a tumor bed boost during radical surgery, then received external-beam radiation therapy (EBRT) at a total dose of 54-60Gy within 6 weeks after surgery, 5 times per week, 1.8-2Gy per time, 30 times in total. The median follow-up time was 20 months (7 -39 months). The primary outcome was the local control (LC) and 2 - year survival rate determined using the Kaplan-Meier method. This study is registered with ClinicalTrials.gov, NCT04278638.

RESULTS

A total of 63 patients consented to participate in the study; 59 males and 4 females, median age was 61 years (40-81 years), 14 patients had supraglottic LAL, 44 patients had glottic LAL and 5 patients had subglottic LAL. 10 patients showed high differentiation and 44 patients showed moderate differentiation and 9 patients showed low differentiation with laryngeal squamous cell carcinoma. 3 patients were in T2N1-2 stage, 40 patients in T3N0-2 stage, and 20 patients in T4N0-2 stage, 48 patients received total laryngectomy and 15 patients received hemilaryngectomy; 16 patients were lymph node-positive and 1 patient developed vascular tumor thrombus after surgery. After surgery combined with IORT and EBRT, the 1- and 2- year LC rates were 98.2% and 93.1 %, respectively, 2-year overall survival rate was 97.4%. Pharyngeal fistula was observed in 1 patient (1. 6 %) and wound infection in 3 patients (4.8%). Radiation Therapy Oncology Group (RTOG) grade 3 pain and RTOG grade 4 dyspnea were noted in one patient (1.6%) and 2 patients (3.2 %), respectively.

CONCLUSION

In summary, our prospective phase II trial proved that the addition of intraoperative radiotherapy as a tumor bed boost to postoperative radiotherapy provided local therapeutic benefit to patients with locally advanced laryngeal cancer. Our data support the safety of this combined therapy. Additional investigation is warranted to determine the role of intraoperative radiotherapy in the local treatment of locally advanced laryngeal cancer.

[Safety and survival analysis of haplo-identical hematopoietic stem cell transplantation in patients with severe aplastic anemia who had previous failure to antithymoglobulin treatment]

Objective: To investigate the safety and efficacy of haplo-identical hematopoietic stem cell transplantation (haplo-HSCT) conditioning with the same dosage form of antithymoglobulin (ATG) in patients with severe aplastic anemia (SAA) failure to ATG. Methods: This was a retrospective cohort study. A total of 65 patients with SAA who failed ATG treatment and received haplo-HSCT conditioning with the same dosage of ATG at the Institute of Hematology, Peking University People's Hospital between July 2008 and October 2020 were included as the ATG treatment failure group. An additional 65 SAA patients who applied ATG for the first time during haplo-HSCT were randomly selected by stratified sampling as the first-line haplo-HSCT group. Baseline clinical data and follow-up data of the two groups were collected. Conditioning-related toxicity within 10 days after ATG application and long-term prognosis were analyzed. The Kaplan-Meier was used to calculate the overall survival rate, and the Log-rank test was applied to compare the rates of the two groups. Results: In the ATG treatment failure group, there were 36 males and 29 females, and the age at the time of transplantation [M (Q1, Q3)] was 16 (8, 25) years. In the first-line haplo-HSCT group, there were 35 males and 30 females, with a median age of 17 (7, 26) years. Within 10 days of ATG application, the incidence of noninfectious fever, noninfectious diarrhea, and liver injury in the ATG treatment failure group was 78% (51 cases), 45% (29 cases), and 28% (18 cases), respectively, and in the first-line haplo-HSCT group was 74% (48 cases), 54% (35 cases), and 25% (16 cases), respectively; the difference between the two groups was not statistically significant for any of these three parameters (all P>0.05). For graft-versus-host disease (GVHD), there was no significant difference between the ATG treatment failure group and the first-line haplo-HSCT group in the development of 100 day Ⅱ to Ⅳ acute GVHD (29.51%±0.35% vs. 25.42%±0.33%), Ⅲ to Ⅳ acute GVHD (6.56%±0.10% vs. 6.78%±0.11%), and 3-year chronic GVHD (26.73%±0.36% vs. 21.15%±0.30%) (all P>0.05). Three-year overall survival (79.6%±5.1% vs. 84.6%±4.5%) and 3-year failure-free survival (79.6%±5.1% vs. 81.5%±4.8%) were also comparable between these two groups (both P>0.05). Conclusions: Compared with no exposure to ATG before HSCT, similar early adverse effects and comparable survival outcomes were achieved in patients with SAA who failed previous ATG treatment and received haplo-HSCT conditioning with the same dosage form of ATG. This might indicate that previous failure of ATG treatment does not significantly impact the efficacy and safety of salvaging haplo-HSCT in patients with SAA.

Early Stereotactic Body Radiotherapy to the Primary Lung Lesion for Patients with Advanced NSCLC Treated with First-Line Systemic Therapy

PURPOSE/OBJECTIVE(S)

Although adding consolidative stereotactic body radiotherapy (SBRT) to systemic therapy improves survival in advanced non-small cell lung cancer (NSCLC), the optimal timing of SBRT remains unclear. This study aimed to explore the clinical outcome of early and delayed SBRT to primary lung lesions of advanced NSCLC patients treated with first-line systemic therapy.

MATERIALS/METHODS

We identified patients with advanced NSCLC who were suitable to receiveSBRT for the primary lung tumors after first-line systemic therapy. All eligible patients were treated with first-line systemic therapy and SBRT for their primary lung lesions. Early SBRT group was defined as patients who received SBRT for their primary lung tumor at the maximal response of systemic therapy. Delayed SBRT group was defined as patients who received SBRT after the occurrence of oligoprogression in primary lung tumor. The primary endpoints were progression-free survival 1 (PFS1, time from start of first-line systemic therapy to disease progression) and PFS2 (time from start of first-line systemic therapy to disease progression after SBRT). Overall survival (OS) and adverse effects (AEs) were secondary endpoints. A two-sided P value of 0.05 was considered statistically significant. All of the statistical analyses were performed with statistical software.

RESULTS

A total of184 patients with advanced NSCLC treated with SBRT for primary tumors were screened, and 49 patients were eligible for enrollment in this study. The median age of the entire cohort was 66 years (range, 37-80 years), and 34 (69.4%) patients were male. Thirty-four patients (69.4%) were treated by target therapy and 15 (30.6%) were treated by chemotherapy and immunotherapy. Of the 49 eligible patients, 28(57.1%) received early SBRT to lung primary tumor and 21(42.9%) received delayed SBRT to lung primary tumor. The early SBRT group showed a significantly prolonged PFS1 as compared with the delayed SBRT group (mPFS1: 30 months vs. 8 months, P<0.001). The median PFS2 of the early SBRT group was longer than that of the delayed SBRT group, but the difference between the two groups did not achieve a statistical significance (mPFS2: 42 months vs. 23 months, P = 0.303). Median OS of both groups has not reached. No severe toxicities (≥grade 3) were observed in early SBRT group and only one patient in the delayed SBRT group experienced grade 3 radiation pneumonitis.

CONCLUSION

Early SBRT to the primary lung lesion significantly improved PFS and is a new potentially effective and tolerable treatment option for patients with advanced NSCLC who had stable disease during first-line systemic therapy.

Comparison of Supraclavicular Surgery plus Radiotherapy vs. Radiotherapy Alone in Breast Cancer Patients with Synchronous Ipsilateral Supraclavicular Lymph Node Metastasis: A Multicenter Retrospective Study

PURPOSE/OBJECTIVE(S)

To evaluate and compare the outcomes of supraclavicular lymph node dissection (SLND) plus radiotherapy (RT) and RT alone for patients with synchronous ipsilateral supraclavicular lymph node metastasis (sISLM).

MATERIALS/METHODS

In all, 293 patients with sISLM across three centers were included. Of these, 85 (29.0%) received SLND plus RT and 208 (71.0%) received RT alone. All patients received preoperative systemic therapy followed by mastectomy or lumpectomy and axillary dissection. Supraclavicular recurrence-free survival (SCRFS), locoregional recurrence-free survival (LRRFS), distant metastasis-free survival (DMFS), disease-free survival (DFS), and overall survival (OS) were evaluated by using the Kaplan-Meier method and multivariate Cox models. Multiple imputation was used for missing data.

RESULTS

The median follow-up duration of the RT and SLND+RT groups were 53.7 and 63.5 months, respectively. For the RT and SLND+RT groups, the 5-year SCRFS rates were 91.7% vs. 85.5% (P = 0.522), LRRFS rates were 79.1% vs. 73.1% (P = 0.412), DMFS rates were 60.4 vs. 58.8% (P = 0.708), DFS rates were 57.6% vs. 49.7% (P = 0.291), and OS rates were 71.9% vs. 62.2% (P = 0.272), respectively. There was no significant effect on any outcome when comparing SLND+RT versus RT alone in the multivariate analysis. Based on four risk factors of DFS, patients were classified into three risk groups: the intermediate- and high-risk groups had significantly lower survival outcomes than the low-risk group. SLND+RT did not improve outcomes of any risk group compared with RT alone.

CONCLUSION

Patients with sISLM may not benefit from SLND. Distant metastasis remained the major failure pattern, especially for intermediate- and high-risk groups with sISLM may not benefit from SLND. Distant metastasis remained the major failure pattern, especially for intermediate- and high-risk groups.

Proposals for the Delineation of Neck Clinical Target Volume Specific to Oral Squamous Cell Cancer Based on Lymph Node Distribution

PURPOSE/OBJECTIVE(S)

To establish the regional lymph node (LN) distribution probability map and draw the neck clinical target volume specific to oral squamous cell cancer (OSCC).

MATERIALS/METHODS

A total of 293 patients with pathologically proven OSCC were enrolled from Jan 2014 to Jun 2022. The patients were divided into two groups according to the ≤1 cm or>1 cm of minimal distance from the lesion's edge to the midline of body. The center point of the LNs with a minimal axial diameter of ≥10 mm was marked on a single treatment planning computed tomography scan. The neck LN levels I to X were based on 2013 updated international consensus guidelines. LN distribution probability maps were established. The relationships between the LN distribution and consensus guidelines were analyzed to propose modifications for clinical target volume boundaries specific to OSCC.

RESULTS

A total of 1033 LNs were marked. Compared with the >1 cm group, The ≤1 cm group has following feature tendencies: strong addiction to smoking and drinking, predilection for tongue and oral floor cancer, larger primary lesion with mainly infiltrative growth pattern, more frequent extra-nodal extension with mainly contralateral LNs. For the ≤1cm group, the distribution probability of LNs was: ipsilateral II (42.67%), ipsilateral Ib (17.35%), contralateral II (11.18%), ipsilateral III (8.74%), contralateral Ib (7.46%), Ia (6.43%). The other group was: ipsilateral Ib (43.14%), ipsilateral II (37.64%), contralateral Ib (4.31%), ipsilateral III (3.92%), contralateral II (3.53%), Ia (0.78%). Accordingly, the proposals for the delineation of neck clinical target volume were: 1. the inferior boundary of level Ia extends until the level of the thyroid cartilage plate; 2. the upper boundary of level Ib descends to the level of the mandibular angle, and the inner posterior boundary only includes the lateral and posterior margin of the submandibular gland within 5mm; 3. the upper boundary of level II changes to the transverse process of the second cervical vertebra, and the posterior boundary retracts to the posterior edge of the levator scapula. 4. the anterior inner border of level IVa contains only the internal jugular arteriovenous sheath.

CONCLUSION

This is the first description of LN topographic spread patterns for OSCC. Optimization of CTV delineation is helpful to improve the treatment outcome and reduce adverse events.

Efficacy and Safety of High-Dose Vitamin C Combined with Total Neoadjuvant Chemoradiotherapy in Locally Advanced Rectal Cancer (HCCSC R02 Study)

PURPOSE/OBJECTIVE(S)

Forpatients with locally advanced rectal cancer (LARC), the standard treatment is fluoropyrimidine (FU) -based neoadjuvant chemoradiotherapy (NCRT) combined with curative surgery. The CAO/ARO/AIO-04 trial and FORWARC trial reported that the addition of oxaliplatin to FU -based NCRT contributed to improve pathologic complete response (pCR), nevertheless, increased the acute therapeutic toxicity. Some studies showed that vitamin C (VitC) had potential benefits on anti-tumor therapy and anti-inflammatory response. Therefore, we conducted this HCCSC R02 study to explore the efficacy and safety of adding a high-dose intravenous VitC to mFOLFOX6/XELOX -based NCRT in LARC.

MATERIALS/METHODS

HCCSCR02 study was designed as a prospective, single-center phase II trial, which including pts aged 18-75 years with stage II/III rectal adenocarcinoma, distance from anus ≤12cm. The enrollment criteria included: staged with MRI as cT3/cT4 or cN1/2, or mesorectal fascia involvement (MRF+), or difficult to preserve the anus. Patients with glucose-6-phosphate dehydrogenase enzyme(G6PD) deficiency were excluded. Pelvic intensity modulated radiation therapy (IMRT) was given in 45-50.4Gy/25-28 fractions. Concurrently, two cycles of chemotherapy (mFOLFOX6 or XELOX) were administered during IMRT, as well as intravenous VitC (24g) delivered daily after the end of each radiation therapy. Additional 2-3 cycles of mFOLFOX6 / XELOX were adopted between the completion of radiotherapy and surgery. The primary endpoint was pCR rate. The secondary endpoints included radiation-related toxicities, overall survival (OS) and disease-free survival (DFS). This study is still recruiting.

RESULTS

From May 15, 2021 to Feb 8, 2023, 19 pts were recruited and finished all the scheduled NCRT, of which the proportion of cT4, cT3, cN2, cN1 were 31.6%, 63.2%, 52.6%, 36.8%, respectively. In addition, 10 pts (52.6%) were diagnosed as MRF+ initially, and 8 pts (42.1%) had a lower primary tumor(≤5cm) who were considered difficult for anal preservation before NCRT. All subjects enrolled were confirmed to be proficient mismatch repair (pMMR). As a result, 18 pts underwent a total mesorectal excision (TME) all with R0-resection, and 8 pts were evaluated as pCR (44.4%, 8/18, confidence interval: 0.246-0.663), 11 as major pathological response rate (MPR) (61.6%, 11/18), respectively. The anus preservation rate in patients with lower diseases was 87.5% (7/8). One case accepted a watch-and-wait strategy because of clinical complete response (cCR). Overall, grade 3 toxicities were observed in 4 pts, including 3 leucopenia (15.8%, 3/19), 2 neutropenia (10.5%, 2/19) and 1 diarrhea (5.3%, 1/19). No grade 4 adverse event was observed.

CONCLUSION

The addition of high-dose VitC to the mFOLFOX6/XELOX-based NCRT in LARC showed a promising pCR, well tolerance, particularly low rate of diarrhea, thus warrants further investigation.

CLINICAL TRIAL INFORMATION

NCT04801511.

Radiation Induced Lung Injury in Rats after Pre-Oxygenation Radiotherapy

PURPOSE/OBJECTIVE(S)

Deep inspiratory breath holding (DIBH) has been widely used during the radiotherapy of thoracic tumors. The main disadvantage of voluntary DIBH is the short duration of each breath hold. The hypocapnia induced by hyperoxia (oxygen concentration > 50%) pre-oxygenation (PreO2) combined with mechanical hyperventilation has been reported to prolong the duration of single breath hold, but its safety remains controversial, especially the sensitivity of lung tissue to radiation damage under hyperoxia exposure has not been elucidated. In this study, we aim to investigate the changes of radiation induced lung injury in rats after PreO2 radiation.

MATERIALS/METHODS

We evaluated the lung tissue of rats at different time points (48h, 2w, 4w, 8w, 12w) after thoracic radiation (15Gy single fraction to the right lung), and sequenced the transcriptome of lung tissue at 48 hours after irradiation. Rat cohorts (n = 7/group): 1. Control (Con); 2. Radiation group (RT); 3. Pre-oxygenation (oxygen concentration > 90%) for 8 hours before thoracic radiation (PreO2).

RESULTS

The inflammatory exudation emerged in the pulmonary interstitium at 48 hours, and reached the most serious alveolitis after four weeks of irradiation (the comparison of alveolitis scores in RT4w vs Con4w and PreO2(4w) vs Con4w, P<0.001) on hematoxylin-eosin staining. While the alveolitis scores in RT group and PreO2 group were not statistically different at each time point. Masson staining showed that the pulmonary fibrosis in the RT group and the PreO2 group reached an obvious pathological change at 12 weeks after irradiation, but the difference between the two groups was not significant. Transcriptome sequencing showed that the number of differential genes in PreO2 vs Con was 559 (302 up-regulated genes and 257 down-regulated genes). The GO enrichment analysis indicated that chromosome segregation was the most significant functional item with P value in the comparative analysis, and the KEGG enrichment analysis suggested that cell division was the most significant enrichment pathway of these differential genes. While there was a small quantity of differential genes in PreO2 vs RT group (3 up-regulated genes and 12 down-regulated genes). Pentose and glucuronate conversions were the most significant enrichment pathway of these differential genes.

CONCLUSION

This study demonstrated that PreO2 radiotherapy did not increase the severity of radiation induced lung injury in rats compared to conventional radiotherapy. Further study should be conducted to confirm these results and to investigate the regulatory mechanism of pneumonia caused by PreO2 radiotherapy.

A Machine Learning Method to Predict Pathological Complete Response of Esophageal Cancer after Neoadjuvant Chemoradiotherapy with Clinicohematological Markers and MR Radiomics: A Multi-Center Study

PURPOSE/OBJECTIVE(S)

Nearly 30% of patients with local advanced esophageal cancer achieved pathological complete response (pCR) after neoadjuvant chemoradiotherapy (nCRT), who may benefit from organ-preservation strategy under accurate prediction of pCR. We aimed to develop and validate machine learning models based on clinicohematological markers and MR radiomics to accurately predict pCR of esophageal cancer after nCRT.

MATERIALS/METHODS

In this multi-center study, eligible patients with esophageal cancer who received baseline MR scan (T2-weighted image) and nCRT plus surgery were enrolled between September 2014 and September 2022 at institution 1 (training set) and between December 2017 and August 2021 at institution 2 (testing set). Pre-nCRT and post-nCRT blood test results were collected to calculate hematological markers. Models were constructed by machine learning based on clinicohematological markers and MR radiomics to predict pCR. Area under the curve (AUC) and cut-off analysis were used to evaluate model performances.

RESULTS

Totally 154 patients (81 in the training set and 73 in the testing set) were enrolled. The combined model integrating pre-nCRT monocyte-to-lymphocyte ratio and 6 radiomics features achieved AUC of 0.800 (95% CI 0.671-0.918) in the testing set, with sensitivity of 79.2% (95% CI 62.5%-95.8%), specificity of 83.7% (95% CI 73.5%-93.9%), positive predictive value of 76.0% (95% CI 62.5%-90.0%), and negative predictive value of 89.6% (95% CI 82.0%-95.8%).

CONCLUSION

A machine learning model based on clinicohematological markers and MR radiomics to predict pCR after nCRT for patients with esophageal cancer was developed and validated, providing a novel tool for personalized treatment. It is necessary to further validate in more large datasets.

Develop a Deep Radiomics Model for Predicting the Response to Neoadjuvant Chemoradiotherapy (nCRT) in Patients with Locally Advanced Esophageal Cancer Using Three-Stage Longitudinal CT Images

PURPOSE/OBJECTIVE(S)

To develop a deep radiomics model for predicting the response to neoadjuvant chemoradiotherapy (nCRT) of patients with locally advanced esophageal cancer using three stage longitudinal CT images.

MATERIALS/METHODS

In this study, 189 patients were used to train our model, 80 patients were used to test the performance of the trained model. All patients enrolled in this study underwent nCRT followed by esophagectomy, and all patients underwent three stage longitudinal CT scans (before nCRT, after nCRT and before esophagectomy). The number of radiomics features for each CT images was 2153, the number of longitudinal radiomic features for each patient was 6459. Then, we used the least absolute shrinkage and selection operator regression for feature importance analysis. After this, the selected features of each stage were feed to the disentangled representation network to explore the relationship between the dynamic changes of tumors before and after nCRT and the pathological complete response (pCR). In addition, in order to further evaluate the effect of the time interval between nCRT and esophagectomy on the response to nCRT, we conducted subgroup analysis on different time frames. The performance of our model was evaluated by area under curve (AUC), accuracy, sensitivity and specificity.

RESULTS

Compared with only using single-stage CT images (the AUC of only using before nCRT CT images, after nCRT CT images, before esophagectomy CT images were 73.27%, 74.21%, and 74.95%, respectively), effectively exploring the dynamic changes of the tumor can achieve better performance in predicting the response to nCRT in the testing cohort (the AUC was 84.29%, 95% CI, 81.14%-87.44%). In addition, the performance of our proposed method outperforms any combinations of two stage CT images (the AUC using the CT images of before nCRT and after nCRT was 77.92%, the AUC using the CT images of before nCRT and before esophagectomy was 79.31%, the AUC using the CT images of after nCRT and before esophagectomy was 80.01%). Finally, the results showed that exploring the dynamic changes of the tumor using the three-stage CT images outperformed using single-stage CT images and any combinations of two-stage CT images in predicting the response to nCRT. The study also found that the time interval between nCRT and esophagectomy had some influence on the accuracy of pCR prediction, with the prediction accuracy tending to increase from 1 to 6 weeks and stabilizing after 6 weeks.

CONCLUSION

By exploring the dynamic changes of tumors, the designed disentangled representation network can effectively predict the response to nCRT of patients with esophageal cancer. In addition, the time interval between nCRT and esophagectomy also has a certain impact on the response to nCRT.

Development and Validation of a Deep Learning-Based Auto-Delineation of Target Volume and Organs at Risk in Pancreatic Cancer Radiotherapy

PURPOSE/OBJECTIVE(S)

The delineation of the clinical target volume (CTV), gross target volume (GTV) and organs at risk (OARs) is a crucial and laborious in pancreatic cancer radiotherapy. In this work, we propose and evaluate a three-dimensional (3D) novel convolutional neural network (CNN) for automatic and accurate CTV, GTV and OARs in pancreatic cancer.

MATERIALS/METHODS

A total of 120 computed tomography (CT) scans patients with pancreatic cancer were collected. A novel 3D CNN network, called ResUNet3D, was developed to achieve auto-delineation. 96 patients chosen randomly were used for training, 12 patients for validation, and 12 patients for testing. Meanwhile, the Dice similarity coefficient (DSC) and 95th percentile Hausdorff distance (HD95%) were used to assess the performance.

RESULTS

The DSC values for the test data were 80.9±8.6%, 77.5±5.6%, 94.5±1.3%, 66.2±13.4%, 73.6±7.6%, 79.0±8.7%, 94.1±1.9%, 94.6±1.4%, 87.3±5.8% for CTV, GTV, liver, duodenum, spinal cord, bowel, kidney left, kidney right, stomach. The corresponding HD95% values were 10.7±6.9mm, 7.8±5.7mm, 11.6±5.6mm, 18.6±5.6mm, 2.7±0.7mm, 17.7±8.6mm, 3.9±1.4mm, 3.7±1.9mm, 13.4±5.7mm, respectively. The average delineation time for one patient's CT images was within 5 seconds.

CONCLUSION

The experimental results demonstrate that the CTV, GTV and OARs delineated for pancreatic cancer by ResUNet3D achieved a close agreement with the ground truth. ResUNet3D could significantly reduce the radiation oncologists' contouring time.

Evaluating the Effects of Bone Marrow Sparing Radiotherapy on Acute Hematologic Toxicity for Patients with Locoregionally Advanced Cervical Cancer: A Prospective Phase II Randomized Controlled Trial

PURPOSE/OBJECTIVE(S)

Bone marrow sparing intensity modulated radiotherapy (BMS-IMRT) can reduce the incidence of acute hematologic toxicity (HT) for locoregionally advanced cervical cancer (LACC) patients receiving concurrent chemoradiotherapy (CCRT), but the norm has been controversial. The purpose of the study was to evaluate the effects of bone marrow (BM) V40 <25% on decreasing the incidence of acute HT in a prospective clinical trial.

MATERIALS/METHODS

A total of 242 LACC patients were recruited from May 2021 to May 2022, who were evenly randomized into BMS-IMRT group and standard IMRT group according to a computer-generated random number list. All patients received pelvic irradiation with concurrent cisplatin (40 mg/m2 weekly), followed by brachytherapy. For patients in BMS-IMRT group, the outer contour of pelvic bone, lumbar spine and left and right femur heads were additionally delineated as a surrogate for BM, and V40 <25% was prescribed. Blood counts were tested weekly, of which nadirs during external beam radiotherapy (EBRT) were graded to assess acute HT as primary observation index. Second observation index were dosimetric parameters of EBRT plan from the dose volume histograms (DVHs). Binary logistic regression model and receiver operating characteristic (ROC) curve were used for predictive value analysis.

RESULTS

Baseline demographic, disease and treatment characteristics were all balanced between BMS-IMRT group and standard IMRT group. BMS-IMRT was associated with a lower incidence of grade ≥2 and grade ≥3 acute HT, leukopenia and neutropenia (72.70% vs 90.90%, P <0.001*; 16.50% vs 65.30%, P <0.001*; 66.10% vs 85.10%, P = 0.001*; 13.20% vs 54.50%, P <0.001*; 37.20% vs 66.10%, P <0.001*; 10.70% vs 43.80%, P <0.001*). Plan target volume (PTV) for all patients satisfied the clinical requirement of V(100%) ≥95%, and conformity and homogeneity were both comparable between 2 groups. BMS also decreased dose delivered to the organs at risk (OARs) including rectum, bladder and left and right femur head. Univariate and multivariate analyses showed that BM V40 was an independent risk factor for grade ≥3 acute HT (odds ratio [OR] = 2.734, 95% confidence interval [CI] = 1.959-3.815, P <0.001*). Cutoff value was 25.036% and area under the curve (AUC) was 0.786. The nomogram was constructed, which was rigorously evaluated and internally cross-validated, showing good predictive performance.

CONCLUSION

BM V40 <25% can reduce the risks of acute HT for LACC patients receiving CCRT while the dose delivery of target volume and other normal tissues were not compromised. With great practicality and applicability, BM V40 <25% is a promising strategy, making BMS-IMRT widespread especially in the area where application of image guided radiotherapy (IGRT) such as 18F-fluorodeoxyglucose positron emission tomography (18FDG-PET)/CT is not popularized. Chinese clinical trial registry (ChiCTR2200066485).

Consolidative Radiotherapy for Residual PET-Avid Disease on Day +30 Post CAR T-Cell Therapy in Non-Hodgkin Lymphoma

PURPOSE/OBJECTIVE(S)

Up to30% of non-Hodgkin lymphoma (NHL) patients achieve a partial response (PR) to anti-CD19 Chimeric Antigen Receptor T-cell Therapy (CART) on day +30. Most PR patients relapse and only 30% achieve spontaneous complete response (CR) without additional therapies. This study is the first to report on the role of consolidative radiotherapy (cRT) for PR PET-avid disease on day +30 post-CART in NHL.

MATERIALS/METHODS

Aretrospective review across 3 institutions from 2018 to 2022 identified 60 patients with B-cell NHL who received CART and achieved PR (Deauville 4-5) with <5 PET-avid disease sites on day +30. Progression-free survival (PFS) was defined from CART infusion to any disease progression. Overall survival (OS) was defined from CART infusion to death. Local relapse-free survival (LRFS), calculated based on the total number of PR sites, was defined from CART infusion to local relapse (LR) in the PR site identified on day +30. cRT was defined as comprehensive (compRT) - treated all PR PET-avid sites - or focal (focRT).

RESULTS

Followingday +30 PET scan, 45 PR patients were observed and 15 received cRT. Only one patient received consolidative systemic therapy and belonged to the cRT group. Prior to CART, bridging RT was given to 13 patients (9 in observation group and 4 in cRT group). There were no significant differences in the pre-CART and day +30 baseline characteristics, including the median size and SUVmax of the PR sites, between the two groups. However, the median number of PR sites on day +30 was higher in the cRT group (2 [range 1-3] vs 1 [range 1-3], p = 0.003). The median equivalent 2 Gy dose was 39.1 (Interquartile range 36.8-41) Gy, and the most common cRT regimen was 37.5 Gy in 15 fractions. The median follow-up was 21 months. Among the observed patients, 15 (33%) achieved spontaneous CR, and 27 (60%) experienced disease progression with all relapses involving the initial PR sites. Among patients who received cRT, 10 (67%) achieved CR, and 3 (20%) had disease progression with no relapses in the radiated PR sites. None of the 10 cRT patients achieving CR relapsed or required subsequent therapies. The 2-year PFS was 80% and 37% (p = 0.012) and the 2-year OS was 78% and 43% (p = 0.12) in the cRT and observation groups, respectively. Patients consolidated with compRT (n = 12) had superior 2-year PFS (92% vs 37%, p = 0.003) and 2-year OS (86% vs 43%, p = 0.048) compared to observed or focRT patients (n = 48). There were no grade 3+ RT-related toxicities. A total of 90 PR sites were identified; 64 were observed and 26 received cRT. Fourteen (22%) observed PR sites achieved spontaneous sustained CR and 42 (66%) experienced LR. Twenty-four (92%) PR sites consolidated with cRT achieved sustained CR and none experienced LR. The 2-year LRFS was 100% in the cRT sites and 31% in the observed sites (p<0.001).

CONCLUSION

NHL patients who achieve PR by PET to CART are at high risk of local progression. cRT for residual PET-avid disease on day +30 post-CART appears to alter the pattern of relapse and improve LRFS and PFS.

Estimating Potential Benefits of Online Adaptive Proton Therapy for Head-and-Neck Cancer: A Retrospective Study

PURPOSE/OBJECTIVE(S)

Proton therapy is highly sensitive to anatomical changes and setup variations in head-and-neck (HN) treatments. To address this issue, proton centers often acquire patient CT images weekly to monitor patient anatomical changes during the treatment course and perform offline plan adaptation when needed. However, offline adaptation cannot fully account for daily setup variations or the anatomical changes occurring with high frequency. There are a few groups endeavoring to develop advanced technologies to enable online adaptive proton therapy (APT). However, the necessity of online APT remains controversial, as it is unknown that whether online APT will significantly improve treatment quality and outcomes compared to offline APT. The purpose of this study is to estimate the clinical potential of online APT in the management of HN cancers in relation to the current offline APT.

MATERIALS/METHODS

Our retrospective study was conducted with four HN patients (35 fractions per patient), who had been treated with intensity modulated proton therapy and had offline adaptation once or twice during their treatment courses. Synthetic CT (sCT) images were generated from 140 daily CBCT images for us to recalculate the dose of the treatment plan in patient's actual treatment anatomy for each treatment fraction and adapt the plan when warranted. These adaptations were assumed to be performed online before treatment delivery to mimic an online APT course. Accumulative doses were calculated for both courses using the CBCT-based sCT images of every fraction for us to compare the target coverage, organ at risk (OAR) sparing, tumor control probability (TCP) and normal tissue complication probability (NTCP). An in-house script was developed to semi-automate this process in a commercial treatment planning system to facilitate our study.

RESULTS

All patients would benefit from online APT to different extents. For the first patient, with OAR doses comparable to the actual offline course, the retrospective online APT course improved dose coverages of the three CTVs from 95.2%, 98.64% and 89.53% to 98.88%, 99.81%, 98.97%, which would lead to a 4.52% improvement in TCP. Similarly, online APT would yield a 2.66% improvement in TCP for the second patient. For the third patient, with comparable CTV dose coverages, the mean doses of right parotid and oral cavity were decreased from 29.52 Gy relative biological effectiveness (RBE) and 41.89 Gy RBE to 22.16 Gy RBE and 34.61 Gy RBE, leading to a reduce of 1.67% and 3.40% in NTCP. The mean dose of right parotid was decreased from 21.71 Gy RBE to 19.37 Gy RBE for the last patient, leading to a reduce of 0.73% in NTCP.

CONCLUSION

Our results showed that online APT could better maintain the treatment plan quality than offline APT for all the four patients, despite their significant anatomical changes. Future investigation will focus on collecting more patient data to obtain statistically significant results and help identify the patients to whom the online APT will be of most benefit.

Preserving Structural Consistency in the Generation of Synthetic CT in Pelvic MR-Only Radiation Treatment Planning

PURPOSE/OBJECTIVE(S)

MR-based synthetic CT (sCT) generation is necessary for MR-only radiotherapy to assist in radiation dose calculation, owing to no electronic density information in MR images. This study investigated the feasibility of synthesizing CT images from magnetic resonance (MR) images using generation antagonism networks (GANs) for MR radiotherapy of rectal cancer. Meanwhile, the transformer module and the contrast learning loss were introduced to improve the sCT.

MATERIALS/METHODS

The data set used in this study was the T2-weighted MR and CT image data of 108 patients with rectal cancer. Three-fold cross-validation was performed on all data sets. The transformer module was introduced into the plain CycleGAN, and the improved Patch Noise Contrastive Estimation (PatchNCE) loss was used as the loss function. The improved PatchNCE loss maintained the structural consistency of the MR and the synthetic CT by ensuring the consistency of the distribution of image patches on the MR-sCT image pair. The 2.5D images were taken as the input of our model, which refers to taking two consecutive adjacent layers in a specific layer. The CT-to-sCT image similarity was evaluated by metrics of mean absolute error (MAE), peak signal-to-noise ratio (PSNR), and Structure Similarity Index Measure (SSIM). The sCT dosimetric accuracy was verified against CT-based dose distributions for the photon plan. Relative dose differences in the planning target volume and organs at risk were computed.

RESULTS

The evaluation indicators of sCT images generated by our model were superior to the plain CycleGAN in the results of the three-fold cross-validation. MAE, PSNR and SSIM of our model were 42.850HU, 26.486 and 0.988, respectively, which were superior to 47.129HU, 25.167 and 0.978 of the plain CycleGAN. In addition, sCT generated by our model exhibited good continuity in the axial direction compared with plain CycleGAN. Furthermore, most of the relative differences in the DVH indicators were less than 1%.

CONCLUSION

The accuracy of sCT can be effectively improved by introducing a transformer module and comparative learning loss function. Moreover, all dosimetric differences were within clinically acceptable criteria for photon radiotherapy, demonstrating the feasibility of the MRI-only workflow for patients with rectal cancer.

Self-reported sleep disorders and the risk of all cancer types: evidence from the Kailuan Cohort study

OBJECTIVES

Previous studies that focussed on sleep disturbance have primarily examined specific aspects of sleep disorders rather than considering overall sleep quality. We aimed to investigate different sleep disorders and their combination as risk factors for different types of cancer.

STUDY DESIGN

Prospective cohort study.

METHODS

In this prospective cohort study, we included 78,232 participants. A self-reported questionnaire was used to address insomnia, daytime sleepiness, snoring, and sleep duration. Overall sleep quality was evaluated by summarising these four sleep parameters. Cox proportional hazards analysis was used to estimate the hazard ratios and their 95% confidence intervals for determining the effect of the overall sleep-quality score and its components on the risk of incident cancer.

RESULTS

During a median follow-up of 5.67 years, 1266 participants were diagnosed with incident cancer. Compared to participants in the best sleep-quality score group, participants in the worst sleep-quality score group had a higher subsequent risk of overall cancer, and colorectal, breast, uterine or uterine cervical, prostatic, kidney, and bladder cancer. Participants with insomnia and snoring status had an elevated risk of head and neck, breast, uterine or uterine cervical, prostatic, kidney, bladder cancer, and lymphoma.

CONCLUSIONS

Poor overall sleep-quality scores as well as poor scores for the scale's components, including insomnia and snoring status, elevated the risk of overall and several specific-site cancers.

TRIAL REGISTRATION

Kailuan Study, ChiCTR2000029767. Registered 12 February, 2020-Retrospectively registered, https://www.chictr.org.cn/showprojEN.html?proj=48316.

30 Gy vs. 45 Gy Consolidative Thoracic Radiation (cTRT) for Extensive Stage Small Cell Lung Cancer (ES-SCLC): A Multicenter, Randomized, Phase 3 Trial

PURPOSE/OBJECTIVE(S)

Consolidative thoracic radiotherapy (cTRT) showed potential benefit to extensive stage small cell lung cancer (ES-SCLC). However, the optimum dose of cTRT is unknown. The purpose of this randomized trial was to compare the effect of 45 Gy in 15 fractions with 30 Gy in 10 fractions cTRT in ES-SCLC.

MATERIALS/METHODS

This phase III, randomized trial was conducted in 12 public hospitals in China. Eligible patients with pathologically confirmed ES-SCLC who responded to 4-6 cycles of etoposide plus cisplatin (EP) or carboplatin (EC) chemotherapy were randomized 1:1 to receive either 30 Gy in 10 fractions or 45 Gy in 15 fractions cTRT. The primary outcome was 2-year overall survival (OS). Secondary outcomes included 2-year progression-free survival (PFS), 2-year local control (LC) and radiation treatment related toxicity. The primary objective was to detect an OS improvement in 45 Gy cTRT group at 2 years from 13% to 26% assuming a two-sided a = 0.05 and power of 85%, with a planned sample size of 186 patients. This trial was registered with Clinical Trials.gov, number NCT02675088.

RESULTS

Between January 15, 2016, and September 20, 2022, 90 patients were randomly assigned either 30 Gy in 10 fractions (n = 50) or 45 Gy in 15 fractions (n = 40) cTRT group. Recruitment to the trial closed early due to slow accrual since first-line chemoimmunotherapy has become the new standard of care for ES-SCLC. The median age of patients was 58 years, 87.8% were male, 76.7% had a smoking history, 95.6% received IMRT, and 58.9% received prophylactic cranial irradiation. At a median follow-up of 39.9 months (IQR 27.2-59.2), there was no significant difference in the 2-year OS between the 45 Gy group and the 30 Gy group, at 43.4% (95% CI 29.3%-64.3%) and 40.0% (95% CI 27.9%-59.1%), respectively (log-rank p = 0.62; HR 1.13 [95% CI 0.69-1.84]). The 2-year PFS was 12.1% (95% CI 4.3%-33.8%) in the 45 Gy group and 9.0% (95% CI 3.2%-25.2%) in the 30 Gy group (log-rank p = 0.25, HR 0.76(95% CI [0.478-1.22]). There were also no significant differences in locoregional recurrence free survival (log-rank p = 0.75; HR 0.888 [95% CI 0.423-1.863]) and distant metastasis free survival (log-rank p = 0.95; HR 1.015 [95% CI 0.624-1.651]) between two groups. No grade 5 toxicity was observed in both groups. Patients treated with higher cTRT dose presented with increased incidence of grade 3+ radiation pneumonitis (10% vs 2%) and hematological toxicity (20% vs 12.5%).

CONCLUSION

This randomized trial did not find a higher probability of survival improvement in patients with ES-SCLC receiving cTRT of 45 Gy in 15 fractions compared with 30 Gy in 10 fractions. In contrast, there was an increase in toxicity, especially radiation pneumonitis. Additional randomized studies investigating the role of cTRT in ES-SCLC after a response to chemoimmunotherapy are warranted.

Improvement of soil acidification and ammonium nitrogen content in tea plantations by long-term use of organic fertilizer

Soil acidification is common in some Chinese tea plantations, which seriously affected growth of tea trees. Hence, it is essential to explore soil remediation in acidified tea plantations for sustainable development of the tea industry. We sought to determine how different fertilizers affect acidified soil and their N transformation in tea plantations. Different fertilizers were used on acidified tea plantation soils for 4 years (2017-2021), and changes in soil pH, indices related to soil N transformation and tea yield were analysed to construct interaction networks of these indices and find which had the largest influence on fertilization. Long-term use of sheep manure reduced soil acidification, increased soil pH, enhanced the number and intensity of N-fixing and ammonifying bacteria, urease, protease, asparaginase and N-acetamide glucose ribosidase activity and nifH gene expression. This treatment reduced the number and intensity of soil nitrifying and denitrifying bacteria, nitrate reductase and nitrite reductase activity, while the expression of amoA-AOA, nirK, nirS, narG and nosZ in turn increased ammonium N content of the soil, reduced nitrate N content, and enhanced tea yield. Topsis index weight analysis showed that ammonium N content in the soil had the largest impact among fertilization effects. Long-term use of sheep manure was beneficial in restoring the balance of the micro-ecosystem in acidified soil. This study provides an important practical basis for soil remediation and fertilizer management in acidified tea plantation soils.

CREB3L2 Regulates Hemidesmosome Formation during Epithelial Sealing

The long-term success rate of dental implants can be improved by establishing a favorable biological sealing with a high-quality epithelial attachment. The application of mesenchymal stem cells (MSCs) holds promise for facilitating the soft tissue integration around implants, but the molecular mechanism is still unclear and the general application of MSC sheet for soft tissue integration is also relatively unexplored. We found that gingival tissue-derived MSC (GMSC) sheet treatment significantly promoted the expression of hemidesmosome (HD)-related genes and proteins in gingival epithelial cells (GECs). The formation of HDs played a key role in strengthening peri-implant epithelium (PIE) sealing. Further, high-throughput transcriptome sequencing showed that GMSC sheet significantly upregulated the PI3K/AKT pathway, confirming that cell adhesion and HD expression in GECs were regulated by GMSC sheet. We observed that the expression of transcription factor CREB3L2 in GECs was downregulated. After treatment with PI3K pathway inhibitor LY294002, CREB3L2 messenger RNA and protein expression levels were upregulated. Further experiments showed that overexpression or knockdown of CREB3L2 could significantly inhibit or promote HD-related genes and proteins, respectively. We confirmed that CREB3L2 was a transcription factor downstream of the PI3K/AKT pathway and participated in the formation of HDs regulated by GMSC sheet. Finally, through the establishment of early implant placement model in rats, we clarified the molecular function of CREB3L2 in PIE sealing as a mechanical transmission molecule in GECs. The application of GMSC sheet-implant complex could enhance the formation of HDs at the implant-PIE interface and decrease the penetration distance of horseradish peroxidase between the implant and PIE. Meanwhile, GMSC sheet reduced the length of CREB3L2 protein expression on PIE. These findings elucidate the potential function and molecular mechanism of MSC sheet regulating the epithelial sealing around implants, providing new insights and ideas for the application of stem cell therapy in regenerative medicine.

Radiotherapy for Patients with Locally Advanced Esophageal Squamous Cell Carcinoma Receiving Neoadjuvant Immunotherapy Combined with Chemotherapy

PURPOSE/OBJECTIVE(S)

With the success of immunotherapy in advanced esophageal cancer, neoadjuvant chemo-immunotherapy (CIT) is being increasingly used for local staged esophageal cancer, especially in the context of clinical trials, which brings similar pCR with neoadjuvant chemoradiotherapy and shows promising results. However, there is still a part of potentially operable patients can't undergo surgery after neoadjuvant chemo-immunotherapy. The follow-up treatment and prognosis of this population remain unclear.

MATERIALS/METHODS

Patients pathologically diagnosed with ESCC, clinical stage T1-3N+M0 or T3-4aNanyM0(AJCC 8th), PS 0-1 were retrospectively enrolled from 1/2020 to 6/2021 in Zhejiang Cancer Hospital. All patients firstly received PD-1 inhibitors (Camrelizumab, Sintilimab or Tislelizumab) plus chemotherapy (albumin paclitaxel,260 mg/m²on day 1 plus carboplatin AUC = 5 on day 1) every 3 weeks for 2-4 cycles. For those patients who did not receive surgery, definitive radiotherapy with 50.4Gy/28F or 50Gy/25F was adopted using VMAT, concurrent with chemotherapy or alone. The concurrent chemotherapy regimens included weekly TC (paclitaxel 50 mg/m 2, d1, carboplatin AUC = 2, d1) or S1 (60mg bid d1-14,29-42). The survival outcomes and treatment toxicity were recorded and analyzed.

RESULTS

A total of 56 eligible patients were finally identified from 558 patients who were treated in department of thoracic surgery, 31 patients showed no response to neoadjuvant CIT (6 with PD and 25 with SD), 25 patients achieved PR but did not receive surgery due to poor performance status or refuse to operation. Median age was 66(IQR 56-72) and 55(98.2%) were males. 12(19.6%) were stage II and 44(80.4%) were stage III. Among all the patients,25 (44.6%) received radiotherapy alone, and 31 (55.4%) received chemoradiotherapy after neoadjuvant CIT. The median follow-up was 11.8 months (IQR 8.6-20.1). The median PFS and OS were 16.5 months (95CI 12.9-21.4) and 18.6 months (95CI 11.2-NA), respectively. In the subgroup analysis, the median PFS for patients with PR to CIT was 20.2 moths (95CI:17.23-NA), and 12.9 moths (95CI: 0.68-20.4) for patients with SD or PD, HR was 0.45 (95CI:0.22- 0.93, P = 0.027). No significant difference was observed for patients received radiotherapy alone or chemoradiotherapy with HR = 1.36(95CI:0.69-2.71, P = 0.37). The most common AEs observed during this study were anemia (98.2%), Leukopenia (83.9%), Thrombocytopenia (53.6%). Adverse events of grade≥3 radiation-induced pneumonitis and esophagitis were 12.5% and 32.1%, especially, 6 patients (10.7%) died from esophageal fistula and 2 patients (3.6%) died from grade 5 pneumonitis.

CONCLUSION

For local advanced ESCC patients after neoadjuvant CIT who did not receive surgery, definitive radiotherapy was an optional treatment strategy. However, those patients with no response to CIT also showed poor response to radiotherapy, and particular attention should be paid to treatment related toxicity, especially esophageal fistula.

Primary Small Cell Carcinoma of the Esophagus in a Large Multicenter Cohort: Prognostic Factors and Treatment Strategies in the Modern Era

PURPOSE/OBJECTIVE(S)

Primary small cell carcinoma of esophageal (PSCCE) is a rare malignancy with aggressive behavior associated with a perceived poor prognosis. Due to its rarity, the clinical characteristics and the optimal clinical management have not yet been defined, therefore, we designed a multicenter retrospective study to analyze the prognostic factors and the impact of treatment on the prognosis of PSCCE patients.

MATERIALS/METHODS

We retrospectively evaluated 704 consecutive patients with PSCCE from five participating centers between April 2008 and July 2021. The PSCCE was diagnosed based on the World Health Organization classification. Treatment strategies included surgery, radiotherapy (RT), or chemotherapy only, and combination of 2-3 treatment modalities (surgery, RT and chemotherapy). The estimated hazard rates provide the trajectory of progression and death overtime. Univariate survival analysis was conducted by using Kaplan-Meier plots, and the log-rank test was used to compare survival differences. Cox regression analysis was used to determine the independent prognostic factors in multivariate analysis.

RESULTS

Overall, 69.0% (486/704) of the patients were male, with a median age of 63 years (range 38-96). Most of the patients were regional lymph node positive (N+, 64.0%), and nearly half with advanced stage (M+, 47.2%). With a median follow-up time of 16 months, 472 patients (67.0%) exhibited disease progression and 429 patients (60.9%) died. Following initial treatment, 85.1% (402/472) of progression/death and 80.1% (344/429) of mortalities occurred within 24 months. Consistently, the maximum annual death and progression/death hazards are highest in the 15.6 months and 9.6 months. The overall survival (OS) rates at 1, 3 and 5 years for all patients were 65.1%, 26.5% and 18.3%, respectively. Univariate survival analysis showed that ECOG score, alcohol abuse, TNM stage, N stage, and M stage were correlated with OS (P <0.05). Multivariate analysis showed that the N stage (HR: 1.378, P = 0.018) and M stage (HR: 1.945, P <0.001) carried independent prognostic factors for OS. In the term of treatment, the OS rates for M- patients treated with combined modality therapy (CMT, surgery±radiotherapy/chemotherapy) were better than those treated with surgery alone or radiotherapy/chemotherapy (3-year OS: 36.7% VS 25.6% VS 32.2%; P = 0.045). The OS rates for M+ patients treated with chemotherapy alone, radiotherapy alone, or radiotherapy combined with chemotherapy were no significant differences (3-year OS: 12.2% VS 19.4% VS 11.1%; P = 0.400).

CONCLUSION

PSCCE is characterized by a high degree of malignancy with high risks of lymphatic and distant metastasis, N and M stages are the most important prognostic factor. In terms of treatment, comprehensive treatment is most likely to benefit patients without distant metastasis.

The Clinical Practice and Dosimetric Outcome of the Manual Adaptive Planning during Definitive Radiotherapy Treatment for Cervical Cancer

PURPOSE/OBJECTIVE(S)

Organ motion is challenging during primary definitive external beam radiotherapy in locally advanced cervical cancer (LACC). Our study evaluated the manual adaptive planning approach three weeks after the treatment started, compared the dosimetric consequences of the manual adaptive plans to the scheduled plans, and explored the clinical factors predicting patients suitable for this replanning strategy.

MATERIALS/METHODS

We analyzed 82 patients receiving primary definitive external beam radiotherapy with weekly online cone-beam computed tomography (CBCT)-based monitoring. The re-CT simulation was performed during treatment to develop a new plan (manual adaptive plan) due to a significant deviation of the clinical target volume (CTV). To evaluate the dosimetric benefit, D98, homogeneity index (HI) and conformity index (CI) for the planning target volume (PTV), as well as D2cc of the bowel, bladder, sigmoid and rectum were compared between the manual adaptive plans and the scheduled ones. The clinical factors influencing target motion throughout treatment were analyzed by chi-square test and logistic regression analysis.

RESULTS

The re-CT simulation was performed after 15 fractions during treatment to develop the manual adaptive plan in 41 patients. The median CI and HI of the manual adaptive plan were significantly superior to the scheduled one (P = 0.001, 0.003, respectively), demonstrating a better dose coverage of the target volume. Compared to the scheduled plans, D98 of the manual adaptive plans increased by 3.3% (P = 0.0002), the average of D2cc to the rectum, bladder decreased 0.267Gy (P = 0.0049) and 0.321Gy (P = 0.0146), respectively. In addition, the chi-square test demonstrated that age (P = 0.024), primary tumor volume (P = 0.015), and parametrial infiltration (P = 0.022) were the clinical factors influencing target motion throughout treatment. Multivariate analysis further identified the large tumor volume (≥50cm3, OR = 3.254, P = 0.039) and parametrial infiltration (OR = 3.376, P = 0.018) as the independent risk factors.

CONCLUSION

We found the most significant organ motion happened after 15 fractions during treatment. The manual adaptive planning of definitive radiotherapy improved the dose coverage and decreased the volume of organs at risk of receiving clinically significant doses of RT in patients with LACC. Patients with bulky mass or with parametrial infiltration were highly suggested to receive manual adaptive planning after 15 fractions during definitive radiotherapy, a timesaving strategy compared to the daily online adaptive radiotherapy without compromising the target dose coverage.

Prediction Analysis of Dose Verification Based on Plan Complexity Metrics during Radiotherapy

PURPOSE/OBJECTIVE(S)

Plan validation in radiotherapy includes pre-treatment and in-treatment validation. It is feasible to leverage plan complexity to optimize validation processes, because some research reports that the consistency between planning and measurement or execution decreases as plan complexity increases. Therefore, starting from the plan complexity, this study comprehensively and systematically explores these factors affecting whether the plan verification is passed or not and the strength of their correlations, so as to establish a regression model and optimize the verification process.

MATERIALS/METHODS

The IMRT and model-based validation information were retrospectively collected for patients who received tumor radiotherapy at our institution from January 2020 to May 2022. The seventy-eight metrics characterizing the plan complexity were calculated and checked for each plan by an in-house developed computing platform. The comparisons of plan verification results under different tumor species and different verification methods were carried out, and the plan complexity metrics was also compared. Subsequently, Spearman correlation analysis between plan complexity and plan validation under different tumor species, different verification methods and different evaluation indexes was analyzed to provide the basis for regression analysis.

RESULTS

One thousand two hundred twenty-six patients were enrolled in the study. The plans in Eclipse TPS were performed by Varian Edge and iX linear accelerators and their verification were executed by EPID, Delat4, and ArcCheck. The gamma index under evaluation index of 3%/3mm, 3%/2mm, 2%/2mm, 1%/1mm were respectively 97.4% (7.1%), 94.8% (10.9%), 86.1% (20.1%), 50.7% (22.6%). The γ and DD of EPID and Detla4 decreased with the increase of TH, and the change of DD was the most significant, while the DTA of Detla4 did not change significantly with TH, and the passing rate of DTA and γ in thoracic and abdominal was the highest in ArcCheck group. Contrast and Variance were the most different between tumor types. The pelvic MIs and MIa were larger than those planned for the other three sites. Except for head and neck CLS and MD, other metrics did not vary significantly among tumor species. The correlation between the metrics characterizing the static characteristics of leaves was more significant for head and neck tumors; the correlation between metrics characterizing the flux complexity were significantly different in pelvic. There was a correlation between plan complexity and γ indicators, and the overall strength was ArcCheck > EPID > Delta4 for head and neck, Delta4 > EPID and ArcCheck for thorax-abdomen, Delta4 and EPID > ArcCheck for pelvic, Delta4 > ArcCheck > EPID for arms and legs.

CONCLUSION

There was a correlation between different plan complexity metrics. Based on this study, it is feasible to predict the verification results based on these complexity metrics, but the regression models were respectively established according to tumor types and validation methods.

Small Samples and Low-Cost Auto-Segmentation Method for Pelvic Organ-at-Risk Segmentation in Magnetic Resonance Images Using Deep-Learning

PURPOSE/OBJECTIVE(S)

In radiotherapy, magnetic resonance (MR) imaging has higher contrast of soft tissue, and no radiation compared with computed tomography (CT) scanning. Due to the high-cost of manual annotation, the deep-learning based automatic organ-at-risk (OAR) and target delineation algorithms are in high-demand, but the collecting of large amounts of high-quality annotated datasets remains difficulty. In this paper, we proposed a low-cost OAR segmentation method with semi-supervised annotation using small annotation samples of pelvic MR images.

MATERIALS/METHODS

This study consisted of 94 patients diagnosed with rectal cancer from April 2018 to March 2021 at Peking University People's Hospital. We used 17 slices of MR images with annotation and 78 slices without annotation to train a deep-learning based segmentation model. The bladder, femoral heads, rectum and small intestine were selected as OAR. Semi-supervised method and ensemble learning were used for generating training set using small sample with annotation. Post-processing algorithm was used to correct the self-annotation data. Two of 14 annotation samples were set as test set. As for un-labeled images, 40 of them were set as semi-supervised annotation train set, the rest were test set. Besides, both 2D and 3D auto-segmentation networks were evaluated.

RESULTS

The dice of bladder, femoral head left and right, rectum and small intestine between segmentation results and reference masks is 0.947, 0.983, 0.981, 0.900, 0.845 only using self-annotation and post-processing method of 2D segmentation model. And the dice of corresponding OAR is 0.871, 0.975, 0.975, 0.783, 0.724 using 3D segmentation network, 0.885,0.982, 0.982, 0.882, 0,814 using 2D segmentation network with supervised method (nnUNet). The 2D model outperformed 3D model with better segmentation performance, shorter inference time and fewer parameters.

CONCLUSION

The results proved that we can train a multi-OAR segmentation model only using small annotation samples and other unlabeled samples. Ensemble learning and post-processing methods are necessary for semi-supervised data annotation. For anisotropy data, 2D model shows better performance than 3D models.

Prospective Feasibility Trial of Vertebral Body Sparing Pencil Beam Scanning Proton Craniospinal Irradiation in Growing Children

PURPOSE/OBJECTIVE(S)

Advanced proton therapy techniques now allow for delivery of craniospinal irradiation (CSI) to the entire brain and thecal sac while sparing many of the anterior vertebral bodies from doses expected to inhibit growth, though this technique has not been prospectively studied. The purpose of this trial is to test the feasibility and robustness of vertebral body sparing (VBS) CSI in children with standard image guidance, to assess the dosimetric and toxicity benefits of this approach, and to report early clinical outcomes.

MATERIALS/METHODS

Children 3-18 years old requiring CSI treatment were eligible for this IRB approved prospective clinical trial. The CSI clinical target volume (CTV) included the brain, entire thecal sac and neural foramina with no expansion. Select anterior vertebral bodies (AVB) could be included at the physician's discretion. The spinal portion of the CTV was treated with PA beam(s) with robust optimization (+/-3.5% range, 5mm positional uncertainty). Daily image guidance included kV/kV imaging. Cone beam CT (CBCT) was acquired weekly after final positioning and a virtual CT (vCT) was created for quality assurance (QA) analysis. Acute toxicity was prospectively assessed weekly during treatment and 1 month after per CTCAE v5.0.

RESULTS

Ten children with a median patient age and CSI dose of 9 years (range 3-16) and 36 Gy (RBE) (range 15-36 Gy (RBE)) were enrolled. Common diagnoses were medulloblastoma (n = 4) and non-germinomatous germ cell tumor (n = 3). Seven patients received prior chemotherapy; 2 patients were treated with palliative intent. Dose statistics for the anterior vertebral body varied according to age, CSI dose and portion of the spine, with the greatest sparing in the lower thoracic and lumbar vertebrae for all patients. Nine patients completed all QA CTs; one patient required a replan due to weight gain. For all remaining patients the treatment was highly robust: CTV V95 reduction at the C-spine, T-spine, and L-spine was 0.0±0.1%, 0.6±1.3%, and 0.8±1.1%, respectively. The highest grade non-hematologic acute toxicity was grade 2 alopecia (n = 9) and grade 2 nausea/vomiting (n = 5). One patient reported transient grade 1 esophagitis during treatment. Hematologic toxicity included >/ = grade 3 lymphopenia in 7 patients, >/ = grade 3 leukopenia in 1 patient, >/ = grade 2 anemia in 6 patients, and >/ = grade 1 thrombocytopenia in 3 patients. Median follow-up is 16.6 months (range 10-36 months). Three patients experience intracranial disease progression: 2 local and 1 distant intracranial failure. There were no failures within the spine.

CONCLUSION

Proton vertebral body sparing CSI targeting the thecal sac only is a highly robust treatment technique and is well tolerated. Weekly CBCT to assess changes in soft tissue posterior to the spine is recommended. Further follow-up is required to assess long-term growth outcomes.

Eosinophil Dynamics during Chemo-Radiation Correlate to Clinical Outcome in Stage II-IVA Nasopharyngeal Carcinoma Patients: Results from a Large Cohort Study

PURPOSE/OBJECTIVE(S)

We investigated the dynamics of eosinophil depletion and recovery during definitive concurrent chemo-radiotherapy (CCRT) and how they affect the prognosis of stage II-IVA nasopharyngeal carcinoma (NPC) patients.

MATERIALS/METHODS

A total of 1225 patients with pathologically proven NPC from 2013 to 2019 were enrolled. Fuzzy C-Means Clustering (FCM) was used to assess trends in eosinophil during CCRT longitudinally and to grade eosinophil decline during treatment in combination with absolute eosinophil counts (AECs) at the end of CCRT. Grade G0 refers to patients with no decreasing trend in eosinophils and AECs >0.05×109 cells/L, grade G1 refers to patients with a decreasing trend in eosinophils or AECs between 0-0.05×109 cells/L, grade G2 refers to patients with a decreasing trend in eosinophils and AECs between 0-0.05×109 cells/L. Progression-free survival (PFS) is the primary outcome measure, with overall survival (OS), distant metastasis-free survival (DMFS), and local recurrence-free survival (LRFS) as secondary outcome measures. A Cox proportional risk model was used to determine the hazard ratio for adverse prognostic effects in declining grades of eosinophil.

RESULTS

During a median follow-up of 4.1 years, 376 (30.69%) patients experienced disease progression events. The grade of eosinophil reduction after CCRT was significantly associated with PFS, OS, and DMFS but not with LRFS. After adjusting for demographics, clinical baseline indicators, tumor characteristics, and treatment characteristics, a 1.57-fold (p = 0.001), 1.69-fold (p = 0.007), and 1.51-fold (p = 0.019) increase in the risk of developing PFS, OS, and DMFS was observed for G1 compared with G0, whereas a 2.4-fold (p < 0.001), 2.76-fold (p < 0.001), and 2.31-fold (p < 0.001) increase in the risk of developing PFS, OS, and DMFS was observed for G2. Moreover, among patients with G0, treatment with CCRT with a cumulative dose of platinum-based chemotherapy < 200 mg/m2 resulted in PFS, OS, and DMFS that were not inferior to CCRT with cumulative doses ≥ 200 mg/m2.

CONCLUSION

Eosinophil is an easily detectable and inexpensive biomarker that may be useful in the clinical setting to aid in assessing the prognosis for standard treatment of NPC.

Residual ctDNA Detection Predicts Benefit From Definitive Chemoradiotherapy and Immune Checkpoint Inhibitors in Locally Advanced NSCLC

PURPOSE/OBJECTIVE(S)

Therapeutic efficacy differs across unresectable locally advanced non-small cell lung cancer (LA-NSCLC) patients receiving definitive chemoradiotherapy (CRT), and the dynamic change in circulating tumor DNA (ctDNA) is closely associated with clinical outcomes. However, evidence for the predictive effect of ctDNA in LA-NSCLC patients with CRT and immunotherapy, the current standard of care, remains limited. It is unclear whether residual ctDNA after definitive CRT can guide clinical decisions on further use of immune checkpoint inhibitors (ICIs) consolidation.

MATERIALS/METHODS

We prospectively included 73 patients with unresectable stage II-III NSCLC. All patients received definitive concurrent or sequential CRT, with the prescribed dose of 60 Gy and ≥2 cycles of platinum-based chemotherapy. Thirty-seven (50.7%) patients further underwent ICIs therapy (18 durvalumab, 9 pembrolizumab, 10 others). Peripheral blood samples were collected from all patients before any treatment (baseline), 1 month after CRT (post-CRT), and at the time of progression. All plasma specimens were analyzed with next-generation sequencing panel of 474 cancer-related genes. Plasma samples with ≥1 variant detected were defined as detectable ctDNA. The primary endpoint was progression-free survival (PFS).

RESULTS

After the median follow-up of 25.4 months, median overall survival (OS) was not reached (NR), and median PFS was 16.7 months (95% CI, 12.4-26.6) for all patients. Compared with baseline, ctDNA abundance significantly decreased after definitive CRT (P<0.001) but relatively increased at progression (P = 0.051). Patients treated with CRT plus ICIs exhibited significantly longer OS (median, NR vs 22.1 months [95% CI, 16.7-NR]; P = 0.002) and PFS (median, 24.8 months [95% CI, 16.1-NR] vs 11.4 months [95% CI, 6.5-NR]; P = 0.016) than those with CRT alone. Post-CRT residual ctDNA was associated with significantly poorer OS (median, 18.3 months [95% CI, 14.8-NR] vs NR; P = 0.002) and PFS (median, 6.5 months [95% CI, 5.6-NR] vs 24.8 months [95% CI, 18.8-NR]; P<0.001), whereas baseline ctDNA predicted neither OS (P = 0.310) nor PFS (P = 0.570). For patients with post-CRT detectable ctDNA, further ICIs therapy brought significant benefit in both OS (median, NR vs 14.8 months [95% CI, 12.0-NR]; P = 0.012) and PFS (median, 16.1 months [95% CI, 5.8-NR] vs 6.2 months [95% CI, 4.2-NR]; P = 0.043). However, in patients with post-CRT ctDNA clearance, there was no significant difference in OS (P = 0.080) or PFS (P = 0.151) between patient with and without ICIs, which suggested less clinical benefit.

CONCLUSION

Post-CRT residual ctDNA predicted worse survival in LA-NSCLC, but indicated more benefit from further ICIs therapy and thereby could facilitate personalization of consolidation immunotherapy. Further prospected studies with large sample size are warranted to validated these findings.

Locoregional radiotherapy improves survival outcomes in de novo metastatic nasopharyngeal carcinoma treated with chemoimmunotherapy

BACKGROUND

We aimed to investigate the efficacy of locoregional radiotherapy (LRRT) in patients with de novo metastatic nasopharyngeal carcinoma (dmNPC) receiving chemotherapy combined with anti-programmed cell death receptor-1 monoclonal antibodies (anti-PD-1 mAbs) as first-line treatment and identify optimal candidates for LRRT.

MATERIALS AND METHODS

We enrolled patients with dmNPC receiving platinum-based palliative chemotherapy and anti-PD-1 mAbs followed or not followed by LRRT from four centers. The endpoints were progression-free survival (PFS), objective response rate (ORR), and overall survival (OS). We used the inverse probability of treatment weighting (IPTW) to balance the baseline characteristics of the LRRT and non-LRRT groups to minimize selection bias before comparative analyses. Multivariate analyses were carried out using the Cox proportional hazards model.

RESULTS

We included 163 patients with dmNPC (median follow-up: 22 months). The median PFS was 20 months, and the ORR was 92.0%; the median OS was not achieved. After IPTW adjustments, patients who received LRRT had a significant survival benefit over those not receiving LRRT (median PFS: 28 versus 15 months, P < 0.001). The Epstein-Barr virus DNA (EBV DNA) level after four to six cycles of anti-PD-1 mAbs [weighted hazard ratio (HR): 2.19, 95% confidence interval (CI) 1.22-3.92, P = 0.008] and LRRT (weighted HR: 0.58, 95% CI 0.34-0.99, P = 0.04) were independent prognostic factors. Patients with undetectable EBV DNA levels after four to six cycles of anti-PD-1 mAbs (early EBV DNA clearance) benefitted from LRRT (HR: 0.41, 95% CI 0.22-0.79, P = 0.008), whereas those with detectable levels did not (HR: 1.30, 95% CI 0.59-2.87, P = 0.51).

CONCLUSIONS

Palliative chemotherapy combined with anti-PD-1 mAbs followed by LRRT was associated with improved PFS in patients with dmNPC, especially for patients with early EBV DNA clearance.

Modelling enzyme inhibition toxicity of ionic liquid from molecular structure via convolutional neural network model

Deep learning (DL) methods further promote the development of quantitative structure-activity/property relationship (QSAR/QSPR) models by dealing with complex relationships between data. An acetylcholinesterase inhibitory toxicity model of ionic liquids (ILs) was established using a convolution neural network (CNN) combined with support vector machine (SVM), random forest (RF) and multilayer perceptron (MLP). A CNN model was proposed for feature self-learning and extraction of ILs. By comparing with the model results through feature engineering (FE), the model regression results based on the CNN model for feature extraction have been substantially improved. The results showed that all six models (FE-SVM, FE-RF, FE-MLP, CNN-SVM, CNN-RF, and CNN-MLP) had good prediction accuracy, but the results based on the CNN model were better. The hyperparameters of six models were optimized by grid search and the 10-fold cross validation. Compared with the existing models in the literature, the model performance has been further improved. The model could be used as an intelligent tool to guide the design or screening of low-toxicity ILs.

Expression of FOXO3 in the skin follicles of goose embryos during embryonic development

1. The Forkhead box O3 (FOXO3) transcription factor is a crucial regulator in controlling cell metabolism, proliferation, apoptosis, migration and response to oxidative stress. However, FOXO3 has not previously been studied much in the embryonic skin follicles of geese.2. This study used Zhedong white geese (Anser cygnoides), Jilin white geese (Anser cygnoides) and Hungarian white geese (Anser anser). The feather follicle structure in the dorsal skin during embryonic stages was examined with haematoxylin and eosin (HE) and Pollak staining. The FOXO3 protein content in the embryonic dorsal skin from feather follicles was detected using western blotting and quantitative real-time PCR.3. The mRNA expression level of FOXO3 in the dorsal skin of Jilin white geese was highly expressed on embryonic day 23 (E23; P < 0.01), while mRNA expression of FOXO3 was highly expressed in the feather follicle of Hungarian white geese at E28 (P < 0.01). The expression of FOXO3 protein mainly concentrated in the early embryonic phase among these goose breeds (P < 0.05). This suggested that FOXO3 plays a crucial role in the development and growth of embryonic dorsal skin of feather follicles. The location of the FOXO3 protein was determined using the IHC technique, which further verified the effect of FOXO3 in the dorsal skin for feather follicles during embryogenesis.4. The study demonstrated the differential expression and localisation of the FOXO3 gene among different goose species. It was speculated that the gene could potentially improve goose feather follicle development and feather-related traits and provide a basis for further understanding of FOXO3 function in the dorsal tissue of goose embryos.

Study on the Dynamic Changes of Myocardial Injury Markers in Radiotherapy for Esophageal Carcinoma and Its Correlation with Cardiac Dosimetry

PURPOSE/OBJECTIVE(S)

It was hypothesized that radiotherapy for esophageal cancer could cause radiation-induced heart damage. To investigate the dynamic changes of myocardial enzyme, high-sensitive troponin T (hs-TnT), N-terminal pro-brain natriuretic peptide precursors (PRO-BNP) and left ventricular ejection fraction (LVEF) during radiotherapy and six months after radiotherapy for middle and lower thoracic squamous cell carcinoma, and to analyze the correlation between these indicators and dose-volume histogram (DVH) parameters of the heart.

MATERIALS/METHODS

A total of 35 patients with thoracic esophageal squamous cell carcinoma who underwent radical concurrent chemoradiotherapy were enrolled in the study. Radiation therapy was performed for up to 6 weeks. All patients received Intensity modulated radiation therapy (IMRT). Total radiation dose was from 50.4Gy to 60 Gy in each patient with a dose of 1.8-2.0 Gy per fraction. Blood samples to determine creatine kinase (CK), creatine kinase isoenzyme MB (CK-MB), lactic dehydrogenase (LDH), alpha-hydroxybutyric dehydrogenase (α-HBDH), hs-TnT, PRO-BNP and LVEF were measured before radiotherapy, during (10th -20th fraction), at the end of radiotherapy, 1, 3, 6 months after radiotherapy. The dynamic changes of the above indexes were analyzed. The correlation between the above indexes and the mean heart dose (Dmean), V5-V60 (dose-volume histograms data were recorded in discrete 5Gy dose levels) of the heart in the course of radiotherapy was also analyzed.

RESULTS

The Serum hs-TNT and LVEF show an upward trend during radiotherapy, at the end of radiotherapy and 6 months after radiotherapy for esophageal cancer. The hs-TnT of patients before, during, at the end of radiotherapy and 1, 3, and 6 months after radiotherapy were 7.2pg/ml, 9.1pg/ml, 9.1pg/ml, 9.0pg/ml, 9.4pg/ml, and 8.1pg/ml, respectively (p<0.05). The LVEF were 63.7%, 62.4%, 62.0%, 62.5%, 62.2%, 61.9% respectively (p<0.05). The pro-BNP showed an upward trend during radiotherapy and gradually returned to normal after radiotherapy. The CK and CK-MB showed a downward trend during radiotherapy and 1 month after radiotherapy, and gradually returned to normal 3 months after radiotherapy. Compared with the low dose group (the average dose of heart < 2000cGy), the high dose group (≥2000cGy) had a greater increase in hs-TNT, pro-BNP and LVEF, and a slower recovery time. There was no correlation between the changes of myocardial enzyme, hs-TnT, PRO-BNP, LVEF and the heart mean dose, V5-V60 during radiotherapy (p>0.05).

CONCLUSION

Cardiac injury induced by concurrent chemoradiotherapy for middle and lower thoracic esophageal cancer can lead to the increase of serum hs-TNT and pro-BNP and the increase of LVEF in the early stage of treatment, and this phenomenon is more obvious in the high-dose group. The hs-TnT and PRO-BNP are sensitive parameters to reflect the heart damage in esophageal cancer radiotherapy, which may provide reference for the heart protection during radiotherapy.

Clinical prior Knowledge-Based One-Shot Learning for Automatic Delineation of Clinical Target Volumes in Adaptation Radiotherapy of Cervical Cancer

PURPOSE/OBJECTIVE(S)

Rapid and accurate delineation of clinical target volumes (CTV) of cervical cancer is the crux to ensure the efficiency and benefits of adaptation radiotherapy (ART). However, contour propagation using deformation image registration (DIR) is difficult to ensure the accuracy of CTV contours due to the significant tumor recession in next fraction, and the tumor progress in each fraction is not considered by conventional automatic delineation methods based on deep learning (DL). Currently, one-shot learning (OSL) is feasible to learn the tumor progress from former fractions to improve the accuracy of automatically delineating CTV.

MATERIALS/METHODS

We retrospectively collected 45 patients with cervical cancer from January 2021 to May 2022 in our department. All patients consist of a pair of planning CT and daily CT in ART. A personalized automatic delineation method based on one-shot learning was developed to delineate CTV in daily CT by learning the clinical prior knowledge from the CTV contours and images of planning CT. The performance of our proposed method was evaluated by dice similarity coefficient (DSC), 95% Harsdorff distance (95HD) and average surface distance (ASD) with human experts, and its automatic delineation performance were compared with DIR and DL in daily CT.

RESULTS

Our automatic delineation method OSL performed the best results in all evaluation metrics (denoted by mean ± standard deviation) as shown in Table 1, it is superior to method DL: 0.92 & 0.90 of DSC, 2.33 mm & 2.68 mm of HD95, 0.68 mm & 0.82 mm of ASD, P < 0.05 for DSC and ASD. Specifically, our method is significantly superior to the automatic delineation results by method DIR: 0.92 & 0.84 of DSC, 2.33 mm & 4.11 mm of HD95, 0.68 mm & 1.52 mm of ASD, P < 0.05 for all. In addition, OSL can significantly overcome the delineation problems in fuzzy boundary and delineation missing and perform better generalization for some unusual images, compared with DIR and DL.

CONCLUSION

We proposed an automatic delineation method based on one-shot learning for CTV of cervical cancer in ART, the results demonstrated that the proposed method could improve the precision and generalization of automatically delineating CTV compared against current popular methods. Therefore, it is potential to improve the quality and efficiency of ART for personalized patients and have a positive impact on tumor control and patient survival.

Improved Prediction of Chemoradiation and Immune Checkpoint Blockade Efficacy with Dynamic bTMB Combined with ctDNA in Unresectable Locally Advanced NSCLC

PURPOSE/OBJECTIVE(S)

Consolidation durvalumab after definitive chemoradiation therapy (CRT) has become the new standard of care for patients with unresectable locally advanced non-small-cell lung cancer (LA-NSCLC). However, only a fraction of patients can benefit from it, and current decision-making procedures have limited accuracy. Blood-based tumor mutational burden (bTMB) is a promising biomarker, but whether bTMB alone or combined with circulating tumor DNA (ctDNA) can predict the efficacy of definitive CRT and immune checkpoint inhibitors (ICIs) in patients with LA-NSCLC remains unclear.

MATERIALS/METHODS

This cohort study enrolled patients diagnosed with unresectable LA-NSCLC from 2018 to 2022. Patients were assigned to the cohort A receiving definitive CRT alone (intensity modulated radiation therapy or volumetric modulated arc therapy with the prescribed dose of 60 Gy, concurrently or sequentially with two or more cycles of platinum-based doublet chemotherapy), or cohort B undergoing definitive CRT and immunotherapy. Peripheral blood specimens were collected before and after CRT and subjected to next-generation sequencing panel to analyze ctDNA and bTMB. The dynamic change in bTMB (∆bTMB) was calculated as the bTMB level after CRT minus the baseline bTMB level. Potential correlations were identified by Spearman's correlation tests and expressed as R coefficients. Time-dependent receiver operating characteristic curves and areas under the curve (AUCs) were employed to evaluate the predictive power of different models on survival.

RESULTS

A total of 73 LA-NSCLC patients were included, with 70 (95.9%) at stage III and 3 at stage II (4.1%). Thirty-six patients (49.3%) assigned to the cohort A were treated with CRT alone and 37 (50.7%) in the cohort B receiving CRT and ICIs. Patients with CRT + ICIs in the cohort B showed significantly improved overall survival (OS; P < 0.01) and progression-free survival (PFS; P = 0.02) than those with CRT alone. Baseline bTMB at cutoff values of 4 to 22 did not predict outcomes (all P > 0.10), while patients with increased bTMB (∆bTMB > 0) after CRT had significantly worse OS and PFS (both P < 0.01) than those with decreased or stable bTMB (∆bTMB ≤ 0). ∆bTMB was independent of the ctDNA level after CRT (P = 0.76, R = -0.04). Patients were further divided into 3 groups based on ∆bTMB and post-CRT ctDNA (∆bTMB > 0/detectable ctDNA vs. ∆bTMB ≤ 0/detectable ctDNA vs. ∆bTMB ≤ 0/undetectable ctDNA), and significant survival differences were observed in the pairwise comparisons of 3 groups (all P < 0.05). The model of ∆bTMB combined with post-CRT ctDNA status exhibited the optimal predictive power on both OS (AUC = 0.80) and PFS (AUC = 0.75) and outperformed each factor, which had been respectively validated in the cohort A and B as well.

CONCLUSION

Dynamic bTMB (∆bTMB) combined with post-CRT ctDNA status is a novel and effective biomarker model of predicting survival outcomes in LA-NSCLC patients treated with CRT ± ICIs, and outperforms each individual feature.

A Model of Type II Collagen-Induced Spondylitis and Arthritis in F1 Hybrid Male Mice

In this study, we tested a new model of ankylosing spondylitis in order to determine its histological and radiological features needed to investigate peripheral arthritis, spondylitis, and formation of the new bone tissues. F1 hybrid male mice (BALB/c×DBA/1), a progeny of spondylitis-susceptible BALB/c male mice and rheumatoid arthritis-susceptible DBA/1 female mice, were immunized intraperitoneally with bovine type II collagen (CII) mixed with adjuvant dimethyldioctadecylammonium bromide. Radiological and histological studies were performed at the peak of swelling, redness, and stiffness. The incidence of peripheral arthritis and spondylitis induced by CII in F1 hybrid mice were 66 and 62%, respectively. X-ray examination revealed bone erosion and spondylitis in the peripheral joints, as well as the formation of new bone tissues in the coccygeal vertebrae and between LIII and LIV vertebrae. The histological study showed lymphocyte and plasma cell infiltration, capillary dilation, congestion, and endochondral ossification of the lumbar vertebrae. This novel model of CII-induced spondylitis in F1 hybrid mice provoked axial and peripheral arthritides inducing chronic inflammation. In this model, the formation of new bone tissue in the stiff spine is characterized by endochondral ossification. The advanced model is an additional and valuable tool for investigation of the autoimmune reactions in spondylitis.

Brachytherapy Dose Prediction Based on Monte Carlo Simulations Using Artificial Neural Networks

PURPOSE/OBJECTIVE(S)

The current brachytherapy dose calculation is still based on the oversimplified water kernel superposition algorithm recommended by AAPM TG43. Monte Carlo (MC) method provides high accuracy in dose calculation. However, the MC simulation is computationally intensive and too slow to use in the time-sensitive clinical workflow. This study aims to develop a fast neural network (SK-UNet) to predict 3D brachytherapy dose distribution calculated by the MC simulations.

MATERIALS/METHODS

We hypothesize that the tracks of Ir-192 inside applicators are essential in dose map prediction and the Selective Kernel Networks (SK) can be employed to emphasize the contribution of the applicator in training. We then included SK in UNet to select appropriate receptive field sizes as needed. The network inputs were CT images of patient anatomy, binary masks of HRCTV, bladder, rectum, and source tracks, and the output was the predicted dose map. Totally, 120 cases were used for training and 30 for testing. All clinically common applicators (e.g., vaginal, tandem and ovoid, multi-channel applicator, free needles, etc.) were involved in the study. Model performance was evaluated by the mean absolute error (MAE) of DVH dosimetric metrics and dose distribution metrics between ground truth (GT) and prediction. A smaller MAE indicated a more accurate dose prediction. Dose distribution metrics include the overdose volume index (ODI), target conformity (TC), dose homogeneity index (DHI), and conformal index (COIN). GT was dose calculated by MC simulations. 3D Gamma analysis was also involved.

RESULTS

As shown in Table 1, compared with GT, SK-Net showed comparable DVH dosimetric metrics with 0.28±0.19 deviation for HRCTV D90%, 0.21±0.16 deviation for bladder D2cc, and 0.25±0.22 deviation for rectum D2cc. In dose distribution metrics, the deviations between GT and prediction were TC = 0.04±0.02, ODI = 0.03±0.03, DHI = 0.02±0.02, and COIN = 0.02±0.03. The gamma passing rate was 93%±6%. The 3D dose map prediction for each patient takes about 6s on average in an NVIDIA GeForce RTX 3060 GPU compared to hours with MC simulations.

CONCLUSION

SK-Net demonstrated comparable performance to the MC simulation but with a significantly shorter execution time, taking only 6 seconds on average. It offered a solution to the trade-off between accuracy and speed and has the potential to serve as an alternative to the time-consuming MC simulation in brachytherapy. The developed technique is believed to have the potential for future application with other types of radiation sources and cancers.

Deep Learning for Automatic Prediction of Lymph Node Station Metastasis in Esophageal Cancer Patients from Contrast-Enhanced CT

PURPOSE/OBJECTIVE(S)

The diagnosis of lymph node (LN) metastasis in computed tomography (CT) is an essential yet challenging task in esophageal cancer staging and treatment planning. Although criteria (e.g., RECIST, morphological/texture features) are proposed to predict LN metastasis, the diagnostic accuracy remains low with sensitivity <50% and specificity <75%, as reported in previous studies. Deep learning (DL) has the potential to address this issue by learning from large-scale labeled data. However, due to the practical surgery procedure in lymph node dissection, it is difficult to pair the metastasis of individual LN reported in the pathology report to the LN instance found in the CT image. Hence, in this study, we first use pathology reports to determine the LNS metastasis, then develop a multiple instance deep learning (MIDL) model to predict lymph node station (LNS) metastasis.

MATERIALS/METHODS

We collected 1200 esophageal cancer patients with preoperative contrast-enhanced CT before surgery. A recently developed automatic mediastinal LNS segmentation model was first applied to segment LNS of 1 to 8 based on the IASLC protocol. For each LNS, the local CT region of interest (ROI) was cropped to generate a station-wise CT patch, where the LNS was labeled as metastatic if at least one metastatic LN was indicated in the pathology report. Using the station-wise CT patch and LNS label, we train a 3D MIDL model, MobileNetV3, to predict LNS metastasis. To better provide the LN position priors in MIDL, LN instances (with a short axis >4mm) were also segmented using an automatic LN detection algorithm and were added to the MIDL model as an auxiliary input. Five-fold cross-validation was conducted to evaluate the MIDL performance.

RESULTS

The MIDL model's performance is summarized in Table 1. The MIDL model incorporating an additional LN instance mask demonstrated a superior overall AUC of 0.7539, surpassing the model without the LN mask input by 2.93%. The specificity was evaluated at a threshold resulting in a recall of 0.7, and the best model outperformed the CT input model in terms of specificity by 2.11%. This highlights the value of including the LN position prior to the MIDL model. Notably, when a threshold was set to result in a specificity of 75%, the best MIDL model demonstrated a significantly higher recall compared to the previously reported clinical diagnostic recall (39.7% vs. 63.21%).

CONCLUSION

We developed a MIDL classification model to predict LNS metastasis using CT scans of 1200 patients. Our findings suggest that the MIDL model can substantially improve LNS metastasis prediction and has the potential to play an essential role in cancer staging, treatment planning, and prognostic analysis.