Phylogenomics illuminates the phylogeny of flower weevils (Curculioninae) and reveals ten independent origins of brood-site pollination mutualism in true weevils

Weevils are an unusually species-rich group of phytophagous insects for which there is increasing evidence of frequent involvement in brood-site pollination. This study examines phylogenetic patterns in the emergence of brood-site pollination mutualism among one of the most speciose beetle groups, the flower weevils (subfamily Curculioninae). We analysed a novel phylogenomic dataset consisting of 214 nuclear loci for 202 weevil species, with a sampling that mainly includes flower weevils as well as representatives of all major lineages of true weevils (Curculionidae). Our phylogenomic analyses establish a uniquely comprehensive phylogenetic framework for Curculioninae and provide new insights into the relationships among lineages of true weevils. Based on this phylogeny, statistical reconstruction of ancestral character states revealed at least 10 independent origins of brood-site pollination in higher weevils through transitions from ancestral associations with reproductive structures in the larval stage. Broadly, our results illuminate the unexpected frequency with which true weevils-typically specialized phytophages and hence antagonists of plants-have evolved mutualistic interactions of ecological significance that are key to both weevil and plant evolutionary fitness and thus a component of their deeply intertwined macroevolutionary success.

[Analysis of long-term outcomes of penetrating keratoplasty for congenital corneal opacity]

Objective: To investigate the long-term outcomes of corneal grafts after penetrating keratoplasty(PK) for congenital corneal opacity(CCO) in children aged 0 to 5 years and the related influencing factors. Methods: It was a retrospective series case study. Data of 39 children (55 eyes) who underwent PK surgery due to CCO in the keratology Department of Beijing Tongren Hospital from April 2014 to April 2018 and were followed up for more than 30 months were collected. Among them, there were 17 males (43.6%) and 22 females (56.4%). The age at operation was (16.2±13.3) months, and the follow-up time was (46.4±13.8) months. Clinical data such as basic information, preoperative diagnosis, operation age, operation method and postoperative complications were recorded. The corneal graft transparency was analyzed according to preoperative diagnosis, corneal neovascularization area, age at surgery, monocular or binocular surgery interval, primary surgery type and further surgery, and postoperative complications were observed. Results: At 12 months, 24 months and the last follow-up after PK, 78.2% (43/55), 70.9% (39/55) and 58.2% (32/55) of the affected eyes had clear corneal grafts, respectively.There was no statistical significance between Peters anomaly and sclerocornea (P>0.05), while the extent of neovascularization in the limbus had a significant effect on corneal graft transparency, and graft opacity was more likely to occur in patients with vessel area exceeding 2 quadrants (P<0.05).The highest corneal graft transparency was found in children aged 1 to 3 years 80.8%(21/26) (P<0.05), followed by children younger than 6 months (7/15).The translucency rate of the corneal graft was higher in patients undergoing unilateral surgery than in those undergoing bilateral surgery (P<0.05).Translucency of corneal graft was higher in children with simple surgery than with combined surgery (P<0.05), however, cataract surgery after PK had no significant effect on corneal graft transparency (P>0.05).The postoperative complications mainly included immune rejection in 19 eyes (34.5%), complicated cataract in 13 eyes (23.6%), glaucoma in 7 eyes (13.2%), persistent corneal epithelial defect in 7 eyes (13.2%). Conclusions: After PK in children with CCO, the transparent rate of corneal grafts decreases gradually with time, but the long-term translucency of corneal grafts can still be obtained. The range of corneal neovascularization, age at the time of surgery, whether the surgery was binocular and whether the surgery was combined had an effect on the transparency of corneal graft.

[Efficacy and safety analysis of an improved overlength biliary stent in the treatment of biliary stricture]

Objective: To evaluate the efficacy and safety of an improved overlength biliary stent in the treatment of bile duct stricture. Methods: Prospective randomized controlled study. Patients with bile duct stricture in Peking University International Hospital from February 2016 to June 2021 were randomly divided into the conventional plastic biliary stents (CPBS) group and the improved overlength biliary stents (IOBS) group by envelope random method. CPBS or IOBS were placed after endoscopic retrograde cholangiopancreatography (ERCP) breast catheterization was successfully conducted and the stenosis length was determined by angiography. The incidence of postoperative complications, median patency time of postoperative stent and reoperation rate within 6 months were compared between the two groups, Kaplan-Meier method was used to draw the survival curve, and log-rank test was conducted to evaluate the safety and efficacy of IOBS in the treatment of bile duct stricture. Results: A total of 90 patients were included. There were 45 patients in IOBS group, including 28 males and 17 females, aged (67.2±11.7) years. There were 45 patients in CPBS group, including 26 males and 19 females, aged (64.6±14.4) years. The patients in the both groups were balanced and comparable. There were no significant differences in success rate of operation, operation time, hospitalization time, operation cost and prospective complication rate between the two groups (all P>0.05). There were no significant differences in the changes of liver function index before and 72 hours after operation between the two groups (both P>0.05). The median patency time of stents in IOBS group was longer than that in CPBS group [M(Q1, Q3), 201(155,246) vs 109(55,167) d, P=0.002].The IOBS group had lower reoperation rate than the CPBS group within 6 months [46.2% (18/39) vs 78.9%(30/38), P=0.003]. Conclusion: IOBS has good safety in the treatment of bile duct stricture and the clinical efficacy is superior to CPBS.

Metformin Antagonizes Radiotherapy-Induced Anti-Tumor Effects via Inhibition of cGAS-STING Pathway Mediated Immune Responses

PURPOSE/OBJECTIVE(S)

Radiotherapy induced anti-tumor effects depend on both direct tumor cell death caused by radiation and immune activation mediated by cGAS-STING pathway. Metformin (MTF), which could augment the tumoricidal efficiency of radiation, is indicated to be a radiosensitizer by basic research. However, several large prospective clinical trials proved otherwise. In present study, we intend to interrogate the effects of MTF on radiotherapy-induced anti-tumor immune responses and try to explain the inconsistent outcomings of radiotherapy combined with MTF in basic research and clinical practice.

MATERIALS/METHODS

To explore the effects of MTF on radiotherapy induced anti-tumor effects, tumor models were established using E0771, B16F10 and LLC cell lines in both immunocompetent and immunodeficient mice. To investigate the composition and function of immune cells in tumor microenvironments, single-cell transcriptome sequencing of CD45+ cells sorted from tumor microenvironments were carried out, and flow cytometry and multiple immunofluorescence analysis were then performed for validation. To reveal the possible mechanisms, tumor cells were subjected to radiotherapy in the presence or absence of MTF in vitro, and RNA-sequencing was then employed followed by subsequent validation with western blotting, real-time qPCR and flow cytometry.

RESULTS

We found that systematic administration of MTF could significantly inhibit radiotherapy-induced anti-tumor effects in immunocompetent mouse models. Single cell sequencing of CD45+ cells sorted from tumor microenvironments and further validation showed that administration of MTF dramatically attenuated the infiltration and cytotoxic capacity of CD8+ T cells after radiotherapy. cGAS-STING pathway in tumor cells was required for maximum efficiency of radiotherapy, while MTF curbed cGAS-STING pathway after radiotherapy in a dose-dependent pattern by enhancing autophagy and reducing cytoplasmic mitochondrial DNA accumulation, which contributed to compromised anti-tumor effects.

CONCLUSION

Our findings indicated that MTF could antagonize radiotherapy-mediated anti-tumor effects by inhibiting the activation of cGAS-STING pathway and subsequent immune responses, which may partially explain the unsatisfied outcomes of radiotherapy combined with MTF in clinical practices. Since the anti-tumor effects of radiotherapy rely not only on the tumor-killing efficiency of radiation but also on systematic immune responses, our findings suggest that cautions are needed when MTF is administrated with radiotherapy in clinical practice.

Real-World Evaluation of Adjuvant Radiotherapy in Upper Tract Urothelial Carcinoma Patients: A Prospective Cohort Study

PURPOSE/OBJECTIVE(S)

Recommendations of adjuvant therapy after surgical resection of UTUC was updated in NCCN guideline of 2021.Adjuvant radiotherapy combined with chemotherapy was recommended for patients of T3-4 or N+. However, the renal insufficiency after RNU limits the use of adjuvant chemotherapy of UTUC. Adjuvant radiotherapy alone may be another option. This study aims to verify the real-world choices and effectiveness of adjuvant therapies in UTUC patients with recurrence risk factors.

MATERIALS/METHODS

Patients with high recurrence factors (T2-4, N+, G3 and multifocal tumor) of UTUC patients after radical nephroureterectomy (RNU) in our hospital since 2020 were prospectively recommended to use adjuvant therapy. Patients' adverse events, recurrence and survival rates were investigated. This trial was registered at Chinese Clinical Trial Registry (ChiCTR2100044477).

RESULTS

Between 2020 and 2022, 195 UTUC patients with recurrence factors had been enrolled. The median follow up time was 13 months. Nearly half of the patients (90 patient) with high-risk factors refused to receive adjuvant treatment. The other 105 patients received adjuvant therapy. Thirty-six patients (34.3%) received adjuvant chemotherapy; 43 patients (41.0%) received adjuvant radiotherapy. Fifteen patients (14.3%) received adjuvant combination therapy (chemo-radiotherapy). The 1-year recurrence-free survival (RFS) rates were59.4% and77.5%, respectively in control group and adjuvant therapy group (P = 0.008). The 1-year overall survival (OS) rates were 89.7% and 98.2%, respectively in control group and adjuvant therapy group (P = 0.011). The 1-year recurrence-free survival (RFS) rates of adjuvant chemotherapy and radiotherapy were 58.6%.and 90.2% (P = 0.003). The combination therapy group had the most serious side effects, grade 3 and 2 hematotoxicity were 40% and 20% respectively. Grade 3 hematotoxicity were 22.2% for adjuvant chemotherapy group. Side effects of adjuvant radiotherapy alone were mild. Only one patient had grade 3 hematotoxicity.

CONCLUSION

Although both NCCN guidelines suggest UTUC patient with more than T2 stage and N+ to receive adjuvant therapy, nearly half of them refused any adjuvant therapies. The prognosis of these patients without adjuvant therapy were poor. The side effects of chemoradiotherapy in UTUC is serious. Adjuvant radiotherapy has less side effects and the effectiveness are equivalent to adjuvant chemotherapy in high risk UTUC patients.

[The comparison between endoscopic and surgical treatment of delayed iatrogenic bile duct injury by propensity score matching]

Objective: To compare the safety and clinical efficacy of endoscopic and surgical treatment of patients with delayed iatrogenic bile duct injury (DBDI) with severity (SG) grade 1 to 2. Methods: The clinical data of 129 patients with SG grade 1 to 2 DBDI who received endoscopic or surgical treatment in the First Hospital of Lanzhou University from November 2007 to November 2021 were retrospectively collected. There were 46 males and 83 females,aged (M(IQR)) 54(22)years(range: 21 to 82 years). The baseline data of the two groups were matched 1∶1 by propensity score matching(caliper value was 0.2). Independent sample t test,rank sum test,χ2 test or Fisher exact probability test were used to analyze the data of the two matched groups. Results: There were 48 patients in each of the endoscopic treatment and surgical groups after matching,and there was no difference in general information between the two groups(both P>0.05). The bile duct injury-repair interval and intraoperative anesthesia complications were not statistically significant between the two groups after matching(all P>0.05). Compared with the surgical group, patients in the endoscopic treatment group had significantly shorter operative time(50 (30) minutes vs. 185 (100) minutes, Z=7.675,P<0.01) and postoperative hospital stay(5 (5) days vs. 12 (7) days, Z=5.848, P<0.01).For safety,there was no statistical difference in the incidence of immediate postoperative complications between the two groups with Clavien-Dindo classification of surgical complications<Ⅲ;the incidence of serious postoperative complications (Clavien-Dindo classification of surgical complications≥Ⅲ) was significantly higher in the surgical group than in the endoscopic treatment group(P=0.012). The incidence of long-term postoperative complications was not statistically different between the two groups(28.1% vs. 20.7%,P=0.562). In terms of efficacy,the postoperative liver function indexes of patients in both groups improved significantly compared with the preoperative period and returned to normal or near normal levels; the postoperative infection indexes of both groups showed an increasing trend,but were within the normal range. Of the 96 patients in both groups,61 obtained follow-up,and the follow-up time was (89.4±48.0)months(range: 3 to 165 months),and there was no statistical difference between the two groups(P=0.079). The probability of excellent long-term follow-up (78.1% vs. 86.2%) was not statistically different between the two groups(P=0.412).In patients with Strasberg-Bismuth type E1,the probability of excellent long-term follow-up was higher in the endoscopic treatment group compared with the surgical group(13/14 vs. 2/5,P=0.037). Conclusions: For DBDI patients with SG grade 1 to 2 and bile duct continuity,endoscopy can be used as the first deterministic treatment. The advantages of endoscopic therapy compared to surgery are the lower incidence of postoperative serious complications,and the shorter duration of surgery and postoperative hospital stay.

Phase I-II Study of Prone Hypofractionated Accelerated Breast and Nodal Intensity Modulated Radiation Therapy

PURPOSE/OBJECTIVE(S)

In patients (pts) with breast cancer, prone radiation therapy (RT) has been shown to reduce heart and lung dose which may decrease late toxicity. Routinely used for whole breast irradiation, its use to treat regional lymph nodes (LNs) is not widespread.

MATERIALS/METHODS

In this phase I-II study, pts treated with partial mastectomy or mastectomy with 1-5 pathologically involved LNs underwent whole breast or post-mastectomy RT plus regional nodal irradiation using IMRT to the supraclavicular and level III axillary LNs. Pts who underwent sentinel LN biopsy (SLNB) alone (no axillary dissection) had the level I and II axillary LNs included in the RT field. 40.5Gy in 15 daily 2.7Gy fractions with daily concomitant 0.5Gy tumor bed boost was prescribed. Normal tissue dose constraints included heart V5Gy<5%, ipsilateral lung V10Gy<20%, contralateral lung V5Gy<15%, ipsilateral brachial plexus (BP) maximal dose (Dmax)<43Gy, spinal cord Dmax≤37.5Gy, spinal cord + 0.5cm Dmax<41Gy, thyroid contralateral lobe Dmax<16Gy, esophagus V30Gy<50% and Dmax≤40.5Gy. The primary endpoints were dosimetric feasibility and incidence of >grade 2 acute toxicity according to CTCAE, v3.0. The secondary endpoint was late toxicity. Exploratory outcomes were local recurrence, disease free survival (DFS), and overall survival (OS).

RESULTS

Between January 2011 to December 2016, 97 pts with stage IB-IIA breast cancer were enrolled. 66 pts underwent partial mastectomy and 31 pts underwent mastectomy. 16 pts had SLNB alone. 33% (95% CI: 23.8%, 43.3%) met all protocol dose constraints. Heart, contralateral lung, spinal cord and esophagus V30Gy constraints were met by all pts. The ipsilateral lung constraint was met in 95% (95% CI: 88.6%, 98.4%) of plans with a mean V10Gy of 9.44% (SD: 6.08). The BP Dmax constraint was exceeded in 31.6% (95% CI: 22.4%, 41.9%) of plans with a mean increase of 2.86 Gy (SD: 7.92 Gy) over target. The esophageal Dmax<40.5Gy constraint was exceeded in 6 plans with an increase in 0.74 Gy (SD: 0.46 Gy) over target. There were no grade 3 acute toxicities meeting the primary toxicity endpoint. Common acute low-grade toxicities by pt included fatigue (grade 1: 54 [56%]; grade 2: 2 [2%]), esophagitis (grade 1: 8 [8%]; grade 2: 2 [2%]), dermatitis (grade 1: 81 [84%]; grade 2: 6 [6%]). At median and maximum follow up of 8.02 (IQR: 3.31) and 13.3 years, respectively, there were 2 local recurrences (2.1%). DFS and OS were 86.6% (95% CI: 78.2%, 92.7%) and 90.7% (95% CI: 83.1%, 95.7%), respectively. The incidence of pts with maximum grade 1, 2 and 3 late toxicities were 39 (40%), 14 (14%), and 2 (2%), respectively. The maximum grade late toxicities included 1 grade 3 retraction and 2 grade 3 asymmetries. There was no brachial plexopathy or pneumonitis.

CONCLUSION

Patients treated with prone hypofractionated hybrid breast/chest wall tangents and IMRT to the regional LNs demonstrate excellent dosimetry to the heart, lungs and spinal cord, minimal acute and late toxicity and excellent clinical outcomes. PMID: 26723552.

Partial Stereotactic Ablative Radiotherapy in Bulky Urinary Tract Malignancy: An Update Clinical Outcomes and Dosimetric Analysis

PURPOSE/OBJECTIVE(S)

Patients with bulky urinary tract malignancy have poor prognosis. Stereotactic ablative radiotherapy (SABR) needs careful consideration in abdominopelvic bulky tumors because of dose constraints on the OARs. We reported updated clinical outcomes to evaluate the safety and efficacy of partial stereotactic ablative radiotherapy(P-SABR) in bulky urinary tract malignancy. The study also aims to investigate the feasibility of P-SABR in dose and biologic effective dose (BED) escalation inside the tumors with equivalent toxicity.

MATERIALS/METHODS

A total of 26 patients with urinary tract malignancy underwent P-SABR radiotherapy from January 2013 to September 2018 were retrospectively analyzed in this study. All the patients were in inoperable locally advanced or metastatic stage with tumor diameter > 4.0 cm. The P-SABR plan consisted of the SABR for gross tumor volume boost (GTVb) and following conventionally fractionated radiotherapy for planning target volume (PTV). The first SABR plan to GTVb was delivered in 15-32Gy/3-5f. The second conventionally fractionated radiotherapy plan to PTV was delivered in 40.0-58.08Gy/15-26f. The total P-SABR plan met the OARs constraints. Local control and overall survival were estimated. Acute and late toxicity were evaluated according to RTOG criteria. Paired conventionally fractionated radiotherapy (CFRT) plans were re-designed for all patients, with the same OARs dose constraints and total dose of PTV margin. Dosimetric and BED parameters were compared in P-SABR and paired CFRT plans.

RESULTS

Median age of the patients was 66.5 years (range, 46-90 years). The tumor treated by P-SABR had a median diameter of 8.4 cm (4.1-19.5 cm) and a median volume of 99.2 cc (23.9-631.8 cc). Median follow-up time was 19.1 months. The local control at 1 and 2 years were 83.2%, 77.3%, respectively. The overall survival at 1 and 2 years were 72.2% ,45.5%, respectively. 6 cases have no local recurrence after 36 months. 4 cases remained alive after 60 months. Local symptoms improved in 15/16 cases after P-SABR. Multivariate analysis showed tumor diameter (≥8cm vs. <8cm) was the independent factor affecting local control and overall survival (P=0.033, P=0.016). No patient was observed radiotherapy directly induced ≥grade 3 toxicity. Compared with the paired CFRT plans, the P-SABR plans had no significant difference in most OAR dose parameters, except for the small intestine/colon V15, V45 with an increase of 14.6 cc, 3.4 cc. However, P-SABR plans increased the dose of PTV Dmean, Dmax by 8.7Gy, 14.4Gy (P < 0.001), respectively. In addition, the dose and BED of GTVb had a significant escalation of 15.8Gy and 30.2Gy (P<0.001) respectively in P-SABR plans.

CONCLUSION

We had reported P-SABR is well-tolerated in bulky urinary tract malignancy in previous study. Updated outcomes showed P-SABR may have long-term local control in these people. Compared with traditional CFRT plans, P-SABR plans escalated the dose and BED inside bulky tumors with equivalent toxicity.

Cardiac Sparing with Volumetric Modulated Arc Therapy Enabled Total Body Irradiation (CS VMAT-TBI)

PURPOSE/OBJECTIVE(S)

Volumetric modulated arc therapy (VMAT) enabled total body irradiation (TBI) has replaced conventional TBI in our institution given the improved treatment accuracy, patient comfort, and dose modulation ability. The risk of cardiovascular disease is several folds higher among transplant patients who receive TBI, likely related to dose to the heart. We hypothesize that a cardiac-sparing (CS) VMAT-TBI technique is feasible and can meaningfully reduce dose to the heart while still adequately covering nearby lymphatic tissue.

MATERIALS/METHODS

VMAT-TBI is delivered via multi-isocentric external beams in a frame-based setup. Heart is contoured as per published guidelines. A lymph node contour, which includes tonsils, neck nodal stations, mediastinal, abdominal, retroperitoneal, and pelvic nodes is created. Coverage of the lymph node contour is prioritized over organ-sparing during inverse optimization; with a goal of V90% greater than 99.5% and mean dose less than 800 cGy for the lymph nodes and heart, respectively. An IRB-approved retrospective review was performed with mean heart dose collected for all patients treated with CS VMAT-TBI and compared to a representative cohort of five patients treated with VMAT-TBI without cardiac sparing.

RESULTS

Thirty-one patients were treated with CS VMAT-TBI between 2020-2022 with a median follow up time of 11.5 months. Mean heart dose was 796 ± 71 cGy in the CS VMAT-TBI compared to 1247 ± 29 cGy in the VMAT-TBI group without cardiac sparing (p < 0.001). Of those treated with CS VMAT-TBI, three patients relapsed; one relapse occurred in bone marrow only, one relapse occurred in bone marrow and cervical, thoracic, and intra-abdominal lymphoid tissues, and one patient was simulated but never received induction therapy due to overt progression. 100-day relapse-free survival and overall survival were 82.5% and 86.2%, respectively. Median survival time has not been met.

CONCLUSION

Cardiac sparing is feasible in VMAT-TBI and is associated with significant decrease in mean heart dose of ∼450 cGy. This is estimated to confer a 33.3% decreased absolute risk for lifetime major coronary events compared to patients treated with VMAT-TBI without cardiac sparing. Although limited by short follow-up time, there does not appear to be a significant risk for early relapse despite de-escalating cardiac tissue, likely due to prioritizing coverage of lymph nodes. Prospective clinical studies are needed to further validate cardiac and other organ at risk sparing VMAT-TBI techniques.

Single-Cell Analysis Reveals the Alteration of Immune Checkpoint Molecules Induced by Radiochemotherapy in Cervical Cancer Microenvironment

PURPOSE/OBJECTIVE(S)

Radiochemotherapy (RCT) could alter the function, activation state, and distribution of immune cells in tumor microenvironment (TME). This study aimed to decipher the alteration of immune checkpoint molecules induced by RCT in the TME of cervical cancer by single-cell RNA sequencing (scRNA-seq).

MATERIALS/METHODS

We analyzed the alterations of immune checkpoint molecules in the TME using scRNA-seq data of 32,116 cells from 3 pairs of tumor biopsies of cervical cancer patients pre- and post-RCT. Uniform Manifold Approximation and Projection was applied to demonstrate the heterogeneity of cell subclusters and differences in the distribution of immune checkpoint molecules. The Wilcoxon rank sum test was used to compare the expression level of the immune checkpoint molecules pre- and post-RCT.

RESULTS

VSIR was mainly expressed on cancer-associated fibroblasts and myeloid cells, of which the level can be reduced by RCT (both P < 0.05). RCT also inhibited the expression of co-inhibitory molecules, such as HAVCR2, TIGIT, CD244, and CD160 on CD4+ T, CD8+ T, and NK cells (all P < 0.05). The expression level of co-inhibitory molecules, LAG3, and co-stimulatory molecules, TNFRSF9 on CD8+ and CD4+ T cells were reduced post-RCT (all P < 0.05). Nonetheless, the expression level of co-stimulatory molecules CD28 was significantly increased on CD4+ and CD8+ T cells post-RCT (all P < 0.05). Intriguingly, the expression level of TNFRSF18 was increased on CD8+ T cells post-RCT while it was reduced on NK cells post-RCT (both P < 0.05).

CONCLUSION

This study unveils that RCT could induce complex alteration of the expression of immune checkpoint molecules on immune cells as well as stromal cells, which may help further understand the mechanism of anti-tumor effect of RCT and optimize treatment strategies.

Impact of Post-Mastectomy Radiotherapy on Cosmesis and Quality of Life after Deep Inferior Epigastric Perforator Flap Breast Reconstruction: A Single Institution Experience

PURPOSE/OBJECTIVE(S)

Immediate breast reconstruction (IBR) yields better cosmetic results and reduce psychological distress than delayed (DBR). Literature data showed better local cosmesis after reconstruction autologous flaps than prothesis. Our aim is to compare cosmetic results and quality of life (QoL) after PMRT delivered either after IBR or DBR with DIEP flap.

MATERIALS/METHODS

We reviewed files of 99 patients (100 DIEPs) treated in our department from January 2000 to December 2019. Patients were divided into 2 groups depending on the treatment sequence: IBR (n = 22) versus DBR (n = 78) followed by PMRT. All the patients had their DIEP flap by the same surgical team. All patients had cosmetic evaluation using Harvard/RTOG cosmesis grading scale. Fifty percent (32 in IBR and 14 in DBR group) of the patients responded to the QoL evaluation using auto questionnaires and BREAST-Q to evaluate breast specific HRQoL and satisfaction. The analysis of cosmetic scores was carried out with a Chi2 test and the analysis of QoL scores with a student test. Kaplan Meier (log-rank test) is used for recurrence-free and overall survival.

RESULTS

Median follow-up was 56 months. Median age of the patients was 48 (28-71). In terms of disease stage: T1-2 (52%), N0 (38%). 86% of the patients had chemotherapy either in neo-adjuvant (26%) or adjuvant (60%) settings. Radiation therapy (RT) delivered a total dose ranged between 45 Gy and 50 Gy using 1.8-2.5 Gy/per fraction. Supra-clavicular and internal mammary chain irradiation was performed in 67% and 33% of the patients respectively. After surgery, 15% had post-operative complications such as DIEP necrosis (n = 8) that delayed RT delivery. Among the 99 patients, 3 died from metastatic evolution and were not included in the cosmetic and QoL analyses. Local recurrence rate was slightly higher after DBR (12.5%) as compared to IBR (3.8%). Loco-regional and metastatic recurrence rates were 4.5% and 4.5% after IBR versus 1.3% and 9% after DBR (p = NS). Disease free and overall survival were 88% and 98% at 5y and 66% and 96% at 10y.Good-to-excellent results were observed in 57% in the IBR vs 67% in the DBR (p = 0.92). There was no impact of previous chemotherapy (p = 0.21), tobacco use at diagnosis (p = 0.27), diabetes (p = 0.86), RT timing (p = 0.53) and endocrine therapy administration (p = 0.67). QoL was evaluated with the BREAST-Q self-evaluation for 5 post operative items: psycho-social, physical, sexual well-being and satisfaction with breast and global cosmetic results. Out of the 99 patients, 46% had responded to the QoL evaluation. We found no statistical difference between the two groups for all the BREAST-Q evaluation items.

CONCLUSION

Our center is considered expert for DIEP reconstructions since its development in end of the nineties. Our data showed no impact PMRT using conventional fractionation (with mainly 1.8 Gy/fraction) on cosmetic results, QoL, and patients' satisfaction regardless of the timing of the breast reconstruction. Additional studies are in progress with updates.

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.

Analysis of Institutional DIBH Coaching Program for Surface Guided-DIBH Patients

PURPOSE/OBJECTIVE(S)

Our institute has implemented a surface guided-DIBH (SG-DIBH) coaching program which involves consultation, pre-treatment (CT-sim) and treatment. We would like to analyze the effectiveness of the program.

MATERIALS/METHODS

A total of 72 left breast cancer patients between 1st Apr 2022 to 9th Dec 2022 were registered for radiation treatment. During consultation, oncologist selected suitable patients based on the following criteria: a) age of 18-70; b) left breast cancer, right breast cancer with internal mammary nodes irradiation or dextrocardia; c) no lung/cardiac disease history & d) volunteer for SG-DIBH technique. The eligible patients were then trained by the coaching therapist using a teaching video and practiced at home. During CT simulation, patients were assessed according to the DIBH evaluation form. The evaluation components included patient's compliancy and understanding, the differences of lateral skin marking (free breathing, FB vs DIBH), duration of breath hold and reproducibility. Patients who passed the evaluation were scanned under both FB and DIBH for SG-DIBH treatment. IMRT-FFF 6 to 7 fields were planned. During SG-DIBH treatment, first 3 fractions and weekly CBCT were taken. Patients were encouraged to continue DIBH practice at home throughout whole course of the treatment and they were given 3 identical survey forms (5 questions) at the beginning, middle and end of treatment. The measure for the success of this coaching program would be number of breath-holds, duration of treatment time, treatment accuracy (CBCT matching) and survey results.

RESULTS

There were 48 patients who were eligible for DIBH coaching program, however, only 24 patients had passed the coaching evaluation and 20 patients were treated with SG-DIBH technique successfully. The mean of number of breath-hold and treatment time was 7 times and 7.9 minutes. Total of 123 CBCT images were studied. The setup errors were (0.242±0.180) cm, (0.152±0.137) cm, (0.202±0.165) cm, (0.684±0.640) degrees, (0.816±0.767) degrees, (0.912±0.707) degrees in lateral, longitudinal, vertical, pitch, roll and yaw directions. According to the survey analysis, the number of times to practice at home decreased as the treatment went by. An improvement was seen in patients' self-evaluation in mastering DIBH technique with proper coaching program (from 60% to 90%). Patients' anxiety in performing DIBH were alleviated greatly towards the end of the treatment (from 47% to 15%). 100% of the patients were willing to go for DIBH treatment if given a second chance and additional suggestions claimed that professional clinical teams and coaching program were important for their DIBH treatment journey.

CONCLUSION

A comprehensive DIBH coaching program can effectively identify SG-DIBH patient's suitability. Patient compliancy, treatment accuracy and treatment experience can be enhanced with good coaching program. The involvement of clinical team from consultation to pre-treatment and treatment stage is essential for a successful SG-DIBH treatment.

Fibulin-1 Regulates Initiation of Successional Dental Lamina

In humans, teeth are replaced only once, and the successional dental lamina (SDL) of the permanent tooth is maintained in a quiescent state until adolescence. Recently, we showed that biomechanical stress generated by the rapid growth of the deciduous tooth inhibits SDL development via integrin β1-RUNX2 signaling at embryonic day 60 (E60) in miniature pigs. However, the mechanism by which RUNX2 regulates SDL initiation within the SDL stem cell niche remains unclear. In the current study, we transcriptionally profiled single cells from SDL and surrounding mesenchyme at E60 and identified the landscape of cellular heterogeneity. We then identified a specific fibroblast subtype in the dental follicle mesenchyme between the deciduous tooth and the SDL of the permanent tooth (DFDP), which constitutes the inner part of the niche (deciduous tooth side). Compared with traditional dental follicle cells, the specific expression profile of DFDP was identified and found to be related to biomechanical stress. Subsequently, we found that RUNX2 could bind to the enhancer regions of Fbln1 (gene of fibulin-1), one of the marker genes for DFDP. Through gain- and loss-of-function experiments, we proved that the biomechanical stress-mediated RUNX2-fibulin-1 axis inhibits the initiation of SDL by maintaining SDL niche homeostasis.

Impact of shift work on dementia: a systematic review and dose-response meta-analysis

OBJECTIVES

Although shift work has been reported as having a link to dementia, evidence remains inconsistent, and a comprehensive dose-response meta-analysis of the association is still lacking. We therefore conducted this meta-analysis to explore the association between shift work and the risk of dementia.

STUDY DESIGN

Systematic review and dose-response meta-analysis.

METHODS

PubMed, Embase, and Web of Science databases were systematically searched. Fixed or random-effects models were used to estimate the summary relative risks (RRs) and 95% confidence intervals (95% CIs). Generalized least squares regression was used to estimate dose-response associations, and restricted cubic splines were used to examine possible linear or non-linear associations.

RESULTS

Five articles (10 studies) with 72,999 participants and 23,067 cases were eventually included in the meta-analysis. The summary RRs and 95% CIs of dementia risk with shift work and night shift work versus daytime work were 1.13 (95% CI: 1.05-1.21, I2 = 46.70%) and 1.13 (95% CI: 1.03-1.24, I2 = 9.20%), respectively. The risk of dementia increased by 1% (RR = 1.01, 95% CI: 1.01-1.02, I2 = 41.3%) with each 1-year increase in the duration of shift work. We found a non-linear dose-response association between the duration of shift work and the risk of dementia (Pnon-linearity = 0.006). Though the shape of the curve was steeper with the duration of shift work <7 years, the increase was more gradual after 7 years.

CONCLUSION

Our findings suggest that shift work may be a risk factor for future dementia and that controlling the length of shift work is a feasible measure that may contribute to prevent dementia.

A Novel Planning and Delivery Technology: Dose, Dose Rate and Linear Energy Transfer (LET) Optimization Based on Spot-Scanning Proton Arc Therapy FLASH (SPLASHLET)

PURPOSE/OBJECTIVE(S)

To achieve a high conformal dose with Linear Energy Transfer (LET) optimized FLASH proton therapy, we introduced a new planning and delivery technique concept, the voxel-wised optimization of LET distribution and dose rate based on scanning arc therapy (SPLASHLET) MATERIALS/METHODS: The algorithm optimizes (1) the clinical dose-volume constraint based on dose distribution and (2) the clinical LET-volume constraint based on LET distribution using Alternating Direction Method of Multipliers (ADMM) with Limited-memory BFGS solver by minimizing the monitor unit (MU) constraint on spot weight and (3) the effective dose-average dose rate by minimizing the accelerator's beam current sequentially. Such optimization framework enables the high dose conformal dynamic arc therapy with the capability of LET painting with voxel-based FLASH dose rate in an open-source proton planning platform (MatRad, Department of Medical Physics in Radiation Oncology, German Cancer Research Center-DKFZ). It aiming to minimize the overall cost function value combined with plan quality and voxel-based LET and dose rate constraints. Three representative cases (brain, liver and prostate cancer) were used for testing purposes. Dose-volume histogram (DVH), LET volume histogram (LVH) dose rate volume histogram (DRVH) and dose rate map were assessed compared to the original SPArc plan (SPArcoriginal).

RESULTS

SPLASHLET plan could offer comparable plan quality compared to SPArcoriginal plan. The DRVH results indicated that SPArcoriginal could not achieve FLASH using the clinic beam current configuration, while SPLASHLET could significantly not only improve V40Gy/s in target and region of interest (ROI) but also improve the mean LET in the target and reduce the high LET in organ at risk (OAR) in comparison with SPArcoriginal (Table 1).

CONCLUSION

SPLASHLET offers the first LET painting with voxel-based ultra-dose-rate and high-dose conformity treatment using proton beam therapy. Such technique has the potential to take full vantage of LET painting, FLASH and SPArc.

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.

Efficacy and safety of atropine in myopic children: A meta-analysis of randomized controlled trials

PURPOSE

To evaluate the safety and efficacy of atropine for childhood myopia and further explore the optimal concentration of atropine, so as to provide more reference for clinical application.

METHODS

PubMed, Embase, Cochrane Library and ClinicalTrials.gov were comprehensively searched for randomized controlled trials (RCTs) up to October 14, 2021. The efficacy outcomes were progression of spherical equivalent (SE) and axial length (AL). The safety outcomes included accommodation amplitude, pupil size and adverse effects. The meta-analysis was performed using Review Manager 5.3.

RESULTS

Eighteen RCTs involving 3002 eyes were included. The results showed that at 6-36 months of treatment, atropine was effective in slowing the progression of myopia in children. At 12 months, the WMD of SE and AL of low-dose atropine was 0.25 diopters (D) and 0.1 millimeter (mm), moderate-dose atropine was 0.44 D and 0.16mm, high-dose atropine was 1.21 D and 0.82mm, respectively, compared with the control group. Similarly, at 24 months, low-dose atropine was 0.22 D and 0.14mm, moderate-dose atropine was 0.60 D, high-dose atropine was 0.66 D and 0.24mm, respectively. Interestingly, we also found that there was no significant difference in the effects of low-dose atropine on accommodation amplitude and photopic pupil size compared with the control group, and the rate of photophobia, allergy, blurred vision and other side effects was similar between the low-dose atropine group and the control group. In addition, atropine appears to be more effective in myopic children in China than in other countries.

CONCLUSIONS

Atropine in various concentrations can effectively slow myopia progression in children, and its effect is dose-dependent, while low-dose atropine (0.01% atropine) appears to be safer.

Single-Cell Dissection of Concurrent Chemoradiotherapy-Induced Immunosenescence in Cervical Cancer

PURPOSE/OBJECTIVE(S)

Immunosenescence could attenuate effective anti-tumor immune response, but it's role in the tumor microenvironment following concurrent chemoradiotherapy (CCRT) in cervical cancer (CC) remains largely unknown. We aimed to investigate CCRT induced immunosenescence and its clinical implications in CC at single-cell resolution.

MATERIALS/METHODS

A total of 11326 cells from single-cell RNA sequencing data derived from five post-CCRT CC tumor samples were analyzed by bioinformatics for immunosenescence. Functional enrichment analysis including Gene Ontology (GO) and Gene Set Variation analysis was performed to identify and assess the molecular heterogeneity of cell subclusters. Kaplan-Meier survival analysis was performed in the bulk RNA-sequencing data included 253 patients with CC obtained from the The Cancer Genome Atlas.

RESULTS

We identified senescent and non-senescent cell clusters in tumor-associated macrophages (TAMs), CD8+ T cells and NK cells after CCRT based on the senescence-related genes expression. GO analysis showed that antigen processing and presentation pathways were enriched in the non-senescent TAMs, while the response to hypoxia and oxidative stress were enriched in the senescent TAMs, which repressed the anti-tumor immunity. We further found that the abundance of senescent TAMs was associated with shorter overall survival (OS) of patients with CC (P<0.001). Moreover, compared to senescent CD8+ T, non-senescent CD8+ T exhibited higher cytotoxicity and exhausted signature scores, and increased enrichment of T cell proliferation, differentiation and activation pathways. In addition, the high proportion of non-senescent NK cell was also associated with better OS of CC patients (P = 0.008).

CONCLUSION

We revealed the potential immune suppressive characteristics of CCRT induced senescent immune cells at single-cell resolution, which provides promising therapeutic targets for CC patients.

Respiratory Motion Compensation Using Xsight Diaphragm Tracking for Liver Tumor in CK Synchrony Treatment: A Feasibility Study

PURPOSE/OBJECTIVE(S)

This study investigates the feasibility of using Xsight Diaphragm Tracking (XDT) for liver tumors located near or in the diaphragm during CyberKnife Synchrony Treatment.

MATERIALS/METHODS

Eight patients (46 fractions) with liver tumors located near or in the diaphragm were reviewed retrospectively. Prior to motion data analysis, baselines were flattened to remove the portions with significant changes and improve accuracy. To reduce the uncertainty about sudden irregular breathing, respiratory data were calculated as a rolling average. The overall tracking accuracy based on the patient-specific respiratory curve was evaluated using E2E testing with CIRS (18023-A) dynamic phantom.

RESULTS

Three main trajectories were observed in this work: Linearity (1/8), Linear radial type (6/8) and Hysteresis (1/1). The mean amplitude was 8.56±4.54 mm, 2.77±2.83 mm, and 4.23±3.92 mm for S-I, L-R, and A-P components. The linear trajectory patient had a more concentrated amplitude distribution. The baseline shifts were 5.88 mm (S-I), 2.53 mm (L-R), and 3.48 mm (A-P). Except for patient 2, all standard deviations of the center phase shift were less than 1 mm. The values of XDT correlation and prediction errors were 1.38±0.65 mm vs. 0.65±0.16 mm (S-I), 1.28±0.48 mm vs. 0.34±0.10 mm (L-R), and 0.96±0.32 mm vs. 0.22±0.072 mm (A-P), respectively. The strong positive correlations were amplitude vs. prediction error, SD of center phase vs. prediction error, and SD of center phase vs. amplitude. The median patient curve-based targeting accuracy was less than 1mm. Additionally, the mean target coverage for all patients with a 3 mm margin was 98.03±1.54%.

CONCLUSION

This study proved that the diaphragm could be used as a tracking surrogate for liver tumors located in or near the diaphragm instead of placing golden fiducial markers. A reduction in motion amplitude and respiration training were necessary during liver SABR treatment, along with respiration control and evaluation.

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.

Homeostatic Balance of Gut Microbiota in Head and Neck Squamous Cell Carcinoma Patients during Radiotherapy

PURPOSE/OBJECTIVE(S)

Radiotherapy is the major treatment for head and neck squamous cell carcinoma (HNSCC). Oral microbiota changes have been described before. However, gut microbiota changes in HNSCC patients who received local radiotherapy remain unclear. We aim to investigate the dynamic change of gut microbiota composition in HNSCC patients undergoing radiotherapy and to construct the radiotherapy related gut microbiota database in HNSCC patients.

MATERIALS/METHODS

We enrolled 47 HNSCC patients who scheduled with radiotherapy solely. Intensity-modulated radiotherapy (IMRT) was the standard radiotherapy technique for all the enrolled patients. The field was irradiated with a total dose of 60-66Gy in 30-33 fractions. Fecal pellets were collected at three time points. Bacterial genomic DNA was isolated using magnetic beads and then analyzed by the Illumina MiSeq Sequencing System based on the V3-V4 hypervariable regions of the 16S rRNA gene.

RESULTS

A total of 194 genera which belonged to 27 phyla were found in 141 samples. Increased abundance of microbiota in diversity and richness was observed in mid-radiotherapy group. Moreover, Bacteroides, Blautia, and Phascolarctobacterium were three main genera in all three groups and the mid-radiotherapy group had the highest relative abundance of Phascolarctobacterium. What's more, most significantly altered bacteria shared the same variation pattern which was increased in mid-radiotherapy while decreased to the almost same level of as pre-radiotherapy in post-radiotherapy group.

CONCLUSION

Local radiotherapy can affect the composition of the gut microbiota in HNSCC patients during the mid-term of radiotherapy. However, self-stabilized ability maintained the gut microbiota homeostasis in the end.

PD-L1 Inhibitors Combined with Thoracic Radiotherapy in First-Line Treatment of Extensive Stage Small Cell Lung Cancer: A Propensity Score-Matched, Real-World Study

PURPOSE/OBJECTIVE(S)

The CREST study showed that the addition of thoracic radiotherapy (TRT) could improve the survival of extensive stage small cell lung cancer (ES-SCLC), but whether TRT can bring survival benefit in the era of immunotherapy is controversial. This study aims to explore the efficacy and safety of adding TRT to the combination of PD-L1 inhibitors and chemotherapy.

MATERIALS/METHODS

Thepatients who received PD-L1 inhibitors combined with platinum-based chemotherapy as the first-line treatment of ES-SCLC from January 2019 to December 2021 were retrospectively collected. According to whether they received TRT, they were divided into two groups, and the follow-up analysis was performed. Propensity score matching (PSM) in with a 1:1 ratio was performed to balance the baseline characteristics of the two cohorts. The endpoints were progression-free survival (PFS) and OS.

RESULTS

A total of 211 patients with ES-SCLC were enrolled, of whom 70 (33.2%) patients received standard therapy plus TRT as first-line treatment, and 141 (66.8%) patients in the control group received PD-L1 inhibitors plus chemotherapy. After PSM, a total of 65 pairs of patients were enrolled in the analysis. There were no significant differences in baseline characteristics between the two groups of patients who received TRT and those who did not. In all patients, the median PFS (mPFS) in the TRT group and the non-TRT groupwere 9.5 months and 7.2 months, respectively, with HR = 0.60 (95% CI 0.41-0.87, p = 0.007). The median OS (mOS) in the TRT group was also significantly longer than that in the non-TRT group (24.1 months vs. 18.5 months, HR = 0.53, 95% CI 0.32-0.85, p = 0.009). Multivariable analysis showed that baseline liver metastasis and bone metastasis were independent prognostic factors for OS. In terms of safety, immunotherapy combined with thoracic radiotherapy increased the incidence of treatment-related pneumonia (p<0.001), most of which were grade 1-2.

CONCLUSION

This real-world study shows that adding TRT to durvalumab or atezolizumab plus chemotherapy significantly improves survival in ES-SCLC. It leads to more treatment-related pneumonia, but most of them can be relieved after symptomatic treatment. This treatment model deserves to be explored in prospective clinical trials.

Impact of Prophylactic Pelvic Lymph Node Irradiation in De-Novo Oligometastatic Prostate Cancer

PURPOSE/OBJECTIVE(S)

To evaluate the impact of prophylactic pelvic nodal irradiation in de-novo oligometastatic prostate cancer treated with radiotherapy (RT) for both primary tumor and all metastatic lesions.

MATERIALS/METHODS

This was a single-center prospective cohort study. De novo oligometastatic prostate cancer patients with RT for both primary tumor and all metastatic lesions were included. Kaplan-Meier method, log rank test and cox regression were used to calculate OS and PFS. PFS included PSA failure, local or distant failure assessed by imaging.

RESULTS

This study analyzed 202 patients from 10/2011 to 1/2022 with median follow-up of 48 months. A total of 126 (62.4%) patients were treated with pelvic lymph node RT. The dose was 47.5 Gy with 1.9 Gy per fraction. Among them, 66 (32.7%) patients were treated with whole pelvic RT (WPRT), which the upper limit was at the aortic bifurcation. 60 (29.7%) patients were treated with mini-WPRT, which the upper limit was at the lower margin of obturator foramen. The incidence of diarrhea (P = 0.038) and leukocyte reduction (P = 0.040) in the WPRT subgroup during radiotherapy was significantly higher than that in the mini-WPRT and non-pelvic RT subgroup. For the whole cohort, the median OS and PFS were not reached. The subgroup analysis showed that the elective pelvic nodal irradiation could improve PFS (P = 0.042). However, there was no difference of PFS between standard WPRT and mini-WPRT.

CONCLUSION

The study suggests that for de-novo oligometastatic prostate cancer, elective pelvic nodal irradiation may improve PFS. For patients who cannot tolerate WPRT, mini-WPRT may be an alternative option. However, it needs to be verified in the prospective RCT study.