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.

Survey of iodized salt coverage in areas with different water iodine concentrations and the iodine status of local women

PURPOSE

There were only two definitions of iodine-deficient (water iodine concentration < 10 μg/L) and iodine-excess areas (water iodine concentration > 100 μg/L) in China before 2020. Areas with water iodine concentration between 10 and 100 μg/L implement the same policy as iodine-deficient areas to provide iodized salt. The definition of iodine-adequate areas was formulated in 2020 for the first time. The paper aims to investigate the coverage rate of iodized salt (CR) in different areas defined according to the latest national standards, evaluate the iodine status of local women, and provide a basis for the revision and improvement of relevant policies.

METHODS

A total of 1948 women aged 18-60 were recruited from the iodine extra-high areas (IEHA), iodine-excess areas (IEA), iodine-adequate areas (IAA), inland iodine-deficient areas (IIDA), and coastal iodine-deficient areas (CIDA). Information on daily diet was collected with the Food Frequency Questionnaire. Drinking water, salt, food, and urine samples were collected and tested in our laboratory. Based on the recommended daily iodine intake, we assessed whether the subjects' daily iodine intake levels were adequate.

RESULTS

The CR and the median urinary iodine concentrations (UICs) were 4.02% and 98.03 μg/L in CIDA, 89.74% and 144.93 μg/L in IIDA, 26.55% and 178.60 μg/L in IAA, 8.78% and 446.5 μg/L in IEA, 3.95% and 605.4 μg/L in IEHA, respectively. The differences among these five areas were statistically significant (P < 0.0001). The daily dietary iodine intakes were mainly from drinking water in IAA (63.92%), IEA (92.29%), and IEHA (92.93%), and were mainly from iodized salt in IIDA (59.22%) and food in CIDA (86.6%).

CONCLUSION

Women in IAA and IIDA were in an adequate iodine state. Women in IEA and IEHA were in an iodine-excess state, and it is necessary to carry out water improvements projects. Women in CIDA were in a slight iodine-deficient state, and health education on scientific iodine fortification should be strengthened to increase iodine intake.

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.

Feature Selection Based on Unsupervised Clustering Mechanism on Multiple-Sequence MRIs for Predicting Neoadjuvant Chemoradiation Response in Locally Advanced Rectal Cancer

PURPOSE/OBJECTIVE(S)

Accurate response prediction allows for personalized cancer management. We developed an unsupervised clustering mechanism to improve effectiveness and efficiency in feature selection operation for accurate patient stratification.

MATERIALS/METHODS

Forty-three locally advanced rectal cancer (LARC) patients underwent neoadjuvant chemoradiation were included, pre-treatment T2 and ADC MRIs were acquired for each patient. An initial feature space consisting of 200 radiomic features extracted from manually delineated GTVs from two sequences of MR images. Additional 960 high-order radiomic features extracted from a 3D convolutional neural network (CNN). To remove redundant and irrelevant features, we developed an unsupervised clustering-based feature selection operation to determine the combination of features with potential best performance. The normal process of feature selection involves searching new feature combinations and training new classifiers for evaluating their performance via an iterative process based on selected feature set, the overall time cost is tremendous. To balance the computational cost and search efficiency, firstly, we proposed an unsupervised clustering analysis metric- Comprehensive Cluster Analysis Index (CCAI) through the K-means algorithm, where the average distances between the sample points and the cluster centroids and so on, to construct a multiple linear regression model. Secondly, we extracted sample points by varying the number of features and feature ratios between radiomic features and 3D-CNN features in the output of feature selection. Thirdly, we optimized the model using the sampling points to calculate the CCAI. Two typical feature combination search algorithms, the random forest recursive feature elimination (RF-RFE) and the differential evolution (DE), were used to perform feature selection with CCAI.

RESULTS

The accuracy, area-under-curve (AUC) and specificity, based on combined 3D-CNN and radiomic features extracted from combined T2 and ADC images, were 0.852, 0.871, and 0.735, respectively. Our experiments illustrated higher predictive power (AUC = 0.846) based on high-order abstract features extracted from the CNN on ADC and T2 images, compared to the traditional radiomic model (AUC = 0.714). Additionally, the predictive models constructed based on radiomics and CNN features extracted from ADC images were more predictable in terms of treatment responses than the radiomic and CNN imaging features extracted from T2 images. The average computational time of DE and RF-RFE were 50.5s and 128.6s in one single computation, the average computational time were 24.2s and 91.3s with CCAI, respectively.

CONCLUSION

We proposed an unsupervised clustering analysis mechanism to improve the effectiveness of feature selection while decreasing its time cost markedly, which highlight the correlation and complementarity between low- and high-level imaging features, achieving better predictive accuracy.

Phase I Trial of 'Re-Priming' Radiation Therapy for Relapsed/Refractory Non-Hodgkin Lymphoma Patients in Incomplete Response after Chimeric Antigen Receptor T-Cell (CAR-T) Therapy

PURPOSE/OBJECTIVE(S)

Inpatients with relapsed/refractory non-Hodgkin lymphoma (R/R NHL) treated with CD19-directed CAR-T, only ∼40% achieve complete response (CR) by day 30 PET/CT evaluation. Of those who do not, the large majority (∼70%) ultimately fail, providing an ideal target for early therapeutic intervention to 're-prime' CAR-T. Preclinical and early clinical studies suggest potential synergy and immune augmentation when combining RT with CAR-T. Here we report the phase I results of a prospective phase I/II clinical trial hypothesizing that early salvage focal RT to poor responding sites of disease after CAR-T in R/R NHL patients is safe (phase I) and will improve conversion to CR by day 90 post-CAR-T PET/CT from 29% (historical control) to 58% (phase II).

MATERIALS/METHODS

Weopened a single-arm open-label phase I/II prospective clinical trial at our institution for R/R NHL patients treated with CD19-directed CAR-T with incomplete response on day 30 post-CAR-T PET/CT scan (defined as Lugano > = 4). The phase I component used a 'Rolling 6' design with 6 patients enrolled concurrently at the "definitive" dose level (40-50 Gy EQD2 [i.e., 30 Gy in 5 fractions], with de-escalation to "palliative" dose level (20-32.5 Gy EQD2 [i.e., 20 Gy in 5 fractions]) if >2 dose-limiting toxicities (DLT) observed. Hypofractionated regimens (i.e., 5 fractions) directed only to residual FDG-avid disease were recommended to minimize lymphopenia and potentially result in a more favorable immune microenvironment. DLT rate was defined within 60 days of RT by CTCAE v5.0 grade 4+ hematologic, grade 3+ dermatitis/burn, pneumonitis, enteritis, or other toxicity attributable to RT, as well as new grade 3+ cytokine release syndrome (CRS) per ASTCT consensus guidelines or grade 3+ neurotoxicity per ASTCT ICANS consensus guidelines for adults.

RESULTS

BetweenApril 2021 and July 2022, 6 patients were enrolled. All 6 patients had diffuse large B-cell lymphoma (DLBCL), with 3/6 (50%) transformed from low-grade follicular lymphoma. 2/6 had primary refractory DLBL, while the other 4/6 had median 2.5 lines of treatment prior to CAR-T. No patient had prior RT to a site of residual FDG-avid disease on day 30 post-CAR-T PET/CT. 5/6 patients were treated to 30 Gy in 5 fractions, with the remainder patient treated to 36 Gy in 10 fractions. No grade 3+ DLTs related to RT were observed in the 60-day post-RT period. RT related toxicities included grad 1 alopecia, grade 1 radiation pneumonitis, grade 1 nausea & vomiting, and grade 2 skin infection.

CONCLUSION

Early salvage focal "definitive" dose RT to sites of incomplete response on day 30 post-CAR-T PET/CT for R/R/ NHL patients was safe with no de-escalation of dose needed. This dose will used in the subsequent phase II component of the trial.

Efficacy of percutaneous cement-augmented screw fixation plus percutaneous kyphoplasty in the management of unstable osteoporotic vertebral compression fractures

OBJECTIVE

The present study was performed to compare the efficacy of percutaneous kyphoplasty (PKP) vs. percutaneous cement-augmented screw fixation plus PKP in the management of unstable osteoporotic vertebral compression fractures (OVCF).

PATIENTS AND METHODS

A total of 197 patients with unstable OVCF treated in the Department of Spine Surgery, Lianyungang First People's Hospital from September 2019 to September 2021 were recruited and assigned via random number table method 1:1 to receive either PKP (group A, n=106) or PKP plus percutaneous cement-augmented screw fixation (group B, n=91). The outcome measures for the evaluation of different surgical methods included visual analogue scale (VAS), the height of the anterior-posterior border of the injured spine, Cobb angle of the posterior convexity, Oswestry disability index (ODI) scores, and Japanese Orthopaedic Association (JOA) scores.

RESULTS

PKP exhibited shorter operative time and length of hospital stay and less intraoperative blood loss vs. PKP plus percutaneous cement-augmented screw fixation (p<0.05). Patients with PKP plus percutaneous cement-augmented screw fixation experienced milder postoperative pain vs. those with PKP alone at 7 days postoperatively, as evidenced by the lower VAS scores (p<0.05). PKP plus percutaneous cement-augmented screw fixation provided more restoration of anterior margin height and posterior convexity Cobb angle vs. PKP alone (p<0.05). Patients with PKP only showed slightly higher Japanese Orthopaedic Association (JOA) scores than those with combined surgery, while the postoperative clinical signs between the two arms were similar (p>0.05).

CONCLUSIONS

Single PKP features the benefits of minimal trauma, simple operation, and rapid postoperative recovery in the treatment of OVCF. PKP plus percutaneous cement-augmented screw fixation for severe OVCF provided distinctly better performance than PKP alone in terms of early pain relief, restoration of vertebral body height, correction of posterior convexity deformity, and firm spinal stability.

The Robotic System for the Treatment of Locally Advanced Cervical Cancer with Stereotactic Body Radiotherapy Boost: Results of a Phantom-Based and Preliminary Study

PURPOSE/OBJECTIVE(S)

To fix uterocervical position, compensate uterocervical intrafraction motion, and thus improve the accuracy of dose delivery based on the robotic system for the treatment of locally advanced cervical cancer with stereotactic body radiotherapy boost.

MATERIALS/METHODS

CT images were acquired after robot arm implanted a fixator with fiducial markers into the cervix of pelvic phantom. The treatment plans were designed by contoured a simulated tumor lesion site. The fiducial markers position was obtained by real-time image guidance system and was registered with digitally reconstructed radiographs to calculate correlation error of six directions. The correlation error was delivered to the robotic arm to precisely adjust the position and posture of the fixator, and thus compensated uterocervical intrafraction movement through the interactive interface of the robotic system. The pressure sensor at the head of the fixator provided real-time feedback on the pressure value at the contact surface between the fixer and the cervix. The correlation error of six directions and the pressure value were extracted and analyzed from the log file.

RESULTS

The data from the log file indicated that the three translational direction correlation error of x, y and z were 0.19mm, 0.20mm and 0.10mm, respectively. The three rotational direction correlation error of roll, pitch and yaw were 0.25°, 0.21° and 0.23°, respectively. With the increase of the relative distance between cervix and pressure sensor, the mean value of pressure variation decreases gradually. When the relative distance is 0.5mm and 3mm, the mean value of pressure variation is approximately 76% and 32%, respectively.

CONCLUSION

The correlation accuracy of the robotic system meets the clinical requirements. The robot arm can fix and monitor the cervical motion in real time during radiotherapy. The robot system adjusts the position of the fixator to correct the uterocervical intrafraction motion error, which is feasible and has good clinical application prospect.