Excess Mortality in Persons with Concurrent HIV and Cancer Diagnoses: A Retrospective Cohort Study.

BACKGROUND: With extended lifespans for people with human immunodeficiency virus (PWH), there is a corresponding increased burden of chronic illnesses, including cancer. Our objective was to estimate the excess mortality for PWH with cancer compared with people without HIV (PWoH), accounting for the higher background mortality in the general PWH population. METHODS: We identified 39,000 PWH and 387,767 demographically-matched PWoH in three integrated healthcare systems from 2000-2016. We estimated excess mortality for PWH with cancer, computed as the cancer mortality rate difference-in-difference comparing PWH and PWoH. We evaluated five cancer groups: any cancer; virus-, human papillomavirus-, and Epstein-Barr virus (EBV)-related cancers; virus-unrelated cancers, and common individual cancers. We fitted a multivariable additive Poisson model to estimate excess mortality for PWH with cancer. RESULTS: PWH with any cancer had excess mortality compared with PWoH (41.3/1000 person-years [py], 95% Confidence Interval [CI] 34.0, 48.7). The highest excess mortality was observed for EBV-related cancers (63.2/1000 py, 95% CI 47.8, 78.7), lung cancer (147.7/1000 py, 95% CI 41.1, 254.3) and non-Hodgkin lymphoma (70.5/1000 py, 95% CI 51.4, 89.6). Excess mortality for PWH was attenuated 2009-2016, and PWH with cancer had no excess mortality 5 years after diagnosis. CONCLUSIONS: PWH in care may have excess mortality from certain cancer types, although disparities may have attenuated over time and do not persist beyond 5 years after diagnosis. IMPACT: Findings may guide improved clinical practice, and suggest further research is needed to investigate whether cancer treatment or other factors contribute to mortality disparities for PWH with cancer.

Financial Improvements From Short Course Adjuvant Vaginal Cuff Brachytherapy in Early Endometrial Cancer Compared With Standard of Care, "SAVE" Trial.

PURPOSE: Early-stage endometrial cancer is often treated with hysterectomy followed by adjuvant vaginal cuff brachytherapy (VCB). Financial toxicity from cancer treatment can impact treatment completion. The Short Course Adjuvant Vaginal Cuff Brachytherapy in Early Endometrial Cancer Compared to Standard of Care trial is a multicenter, prospective randomized trial of standard of care (SoC) VCB doses delivered in 3 to 5 fractions per the physician's discretion compared with a 2-fraction course. We report on secondary cost endpoints, quantifying the financial impacts of shorter treatment courses on institutions and participating patients. METHODS AND MATERIALS: Technical (TechCs), professional, and total charges (TotCs) were collected prospectively and are reported as raw and Medicare-adjusted charges per patient. Distance to the treatment center and the median income for each patient's zip code were estimated. The Mann-Whitney U statistic, t test, and X2 test were used to compare characteristics between the 2 groups. RESULTS: One hundred eight patients were analyzed. SoC VCB was delivered in 3, 4, and 5 fractions for 27 of 54 patients (50%), 11 of 54 (20%), and 16 of 54 (30%), respectively. The median total distance traveled per patient for SoC versus experimental arms was 213 versus 137 miles (p = .12), and the median cost of commute for patients was $36.3 versus $18.0 (p = .11). Compared with 2-fraction treatment, 5-fraction treatment resulted in longer travel distances (median, 462 vs 137 miles; p < .01) and increased travel costs (median, $59.3 vs $18.0; p ≤ .01). Unadjusted raw professional charges in USD per patient did not differ between SoC versus experimental arms ($9159 vs $7532; p = .19). TechCs were significantly higher in the SoC arm ($35,734 vs $24,696; p ≤ .01), as were TotCs ($44,892 vs $32,228; p < .01;). Medicare-adjusted TechCs and TotCs were higher for the SoC arm. CONCLUSIONS: Two-fraction VCB resulted in fewer treatments per patient, reduced cost of travel compared with longer courses, and an adjusted reduction in health care expenditures compared with SoC.

Pharmacodynamic Activity of [18F]-Fluorthanatrace Poly(ADP-ribose) Polymerase Positron Emission Tomography in Patients With BRCA1/2-Mutated Breast Cancer Receiving Talazoparib.

PURPOSE: We tested the ability of [18F] fluorthanatrace (FTT), a radiolabeled analog of poly(ADP-ribose) polymerase (PARP)-1 inhibitors, to demonstrate target engagement on positron emission tomography (PET) scans from patients with newly diagnosed primary breast cancer receiving the PARP inhibitor (PARPi) talazoparib. METHODS: Seven patients with germline BRCA1/2 pathogenic variants underwent [18F]FTT PET-computed tomography scanning at baseline, and five underwent repeat scanning 14 days after talazoparib initiation. Maximum uptake on PET was quantified in the primary tumor, involved nodes, contralateral pectoralis muscle, and lumbar vertebra body level 3, and compared between the two time points. RESULTS: Blocking of [18F]FTT was observed on the second scan. Potentially strong but nonsignificant correlations were found between changes in tumor volume (on ultrasound at 1 month v baseline) and percentage changes in tumor-to-muscle uptake ratio at 14 days from baseline (Spearman rank correlation coefficient r = 1; P = .083); and between the highest-grade hematologic toxicity and baseline bone marrow-to-muscle (B/M) uptake ratio (r = 0.72; P = .068) and percentage change in B/M ratio at 14 days from baseline (r = 0.87; P = .058). CONCLUSION: We conclude that [18F]FTT can image target engagement by PARPi, but larger studies are needed to determine whether [18F]FTT uptake can predict response to PARPi and whether uptake of [18F]FTT in bone marrow may be an early predictor of hematologic toxicity.

The Value of Patient-Reported Outcomes to Predict Symptom Burden and Health-Related Quality of Life After Chemoradiation for Cervical Cancer: A Prospective Study.

PURPOSE: Patients with cervical cancer undergoing chemoradiation have high symptom burden. We performed an analysis of prospectively collected data on patient-reported outcomes to determine characteristics predictive of poor treatment experience. METHODS AND MATERIALS: Between 2021 and 2023, we prospectively collected data on patient-reported outcomes from patients with cervical cancer undergoing definitive chemoradiation. The European Organization for Research and Treatment of Cancer (EORTC)-Quality of Life Question-Core 30 and the EORTC-Quality of Life Question-Cervical Cancer module were completed at baseline (BL) and at the end of treatment (EOT). Poor treatment experience was defined as EOT poor health-related quality of life (HRQOL), low physical function, or significant overall symptom burden. Predictive factors analyzed included demographic, clinical, and disease-specific factors and BL financial toxicity, depression, social function, and emotional function. Receiver operating characteristic analysis provided appropriate predictive cutoff values. Univariable and multivariable (MVA) linear regression analyses were performed. RESULTS: Forty-nine patients completed BL and EOT questionnaires. Median age was 43 years (range, 18-85 years). Most patients (59%) had stage III disease. BL financial toxicity ≥66.7, depression ≥66.7, social function ≤50, and emotional function ≤58 on the EORTC linear transformed scale of 0 to 100 were significant predictors for poor treatment experience (p ≤ .04) based on receiver operating characteristic analysis. On MVA, poor BL social function was associated with reduced EOT HRQOL (ß, -9.3; 95% CI, -16.1 to -2.6; p < .008), decreased physical function (ß, -24.4; 95% CI, -36.3 to -12.6; p < .001), and high symptom burden (ß, 26.9; 95% CI, 17.5-36.3; p < .001). Earlier disease stage predicted decreased symptom burden (ß, -6.7; 95% CI, -13.1 to -0.3; p = .039). BL financial toxicity was a significant predictor in univariable analysis (p = .001-.044) and showed a significant interaction term on MVA (p = .024-.041) for all 3 domains of poor treatment experience. Demographic and treatment-related factors were not predictive. CONCLUSIONS: Patients with cervical cancer with poor BL social function or high financial toxicity were at risk for increased symptom burden and poor HRQOL. Screening for these factors provides an opportunity for early intervention to improve treatment experience.

Single-fraction radiation retreatment for bone metastases: role of a rapid access clinic.

OBJECTIVES: This study investigates retreatment rates in single-fraction radiation therapy (SFRT) for painful bone metastasis in patients with limited life expectancy. We compared retreatment-free survival (RFS) in patients from a rapid access bone metastases clinic (RABC) and non-RABC patients, identifying factors associated with retreatment. METHODS: In this observational study, we analysed RABC patients who received SFRT between April 2018 and November 2019, using non-RABC SFRT patients as a comparison group. Patients with prior or perioperative radiation therapy (RT) were excluded. The primary endpoint was same-site and any-site retreatment with RT or surgery. Patient characteristics were compared using χ2 and Student's t-tests, with RFS estimates based on a multistate model considering death as a competing risk using Aalen-Johansen estimates. RESULTS: We identified 151 patients (79 RABC, 72 non-RABC) with 225 treatments (102 RABC, 123 non-RABC) meeting eligibility criteria. Of the 22 (10.8%) same-site retreatments, 5 (22.7%) received surgery, 14 (63.6%) received RT and 3 (13.6%) received both RT and surgery. We found no significant differences in any-site RFS (p=0.97) or same-site RFS (p=0.11). CONCLUSIONS: RFS is high and similar comparable in the RABC and non-RABC cohorts. Retreatment rates are low, even in patients with low Eastern Cooperative Oncology Group scores.

Five-Year Outcomes of a Phase 1/2 Trial of Accelerated Partial Breast Irradiation Using Proton Therapy for Women With Stage 0-IIA Breast Cancer.

Purpose: We report the results of a phase 1/2 trial of external beam partial breast radiation using proton therapy. Methods and Materials: Eligible patients included stage 0-IIA breast cancer pTis-T2, N0, and size ≤3 cm. Proton beam radiation was used to deliver 3.85 Gy twice daily to 38.5 Gy. The phase 1 portion determined feasibility based on criteria of successful plan creation, treatment delivery, and acute toxicity grade ≥3 in ≤20% of patients. The phase 2 portion had efficacy goals of acute toxicity grade ≥3 in ≤20% of patients and observing physician-rated cosmesis of excellent or good >85% of patients at 2 years. Results: From April 2013 to March 2015, there were 12 patients enrolled onto the phase 1 portion, and the preplanned analysis of feasibility was met in all 4 required criteria. From July 2015 through December 2019 there were 28 patients with 29 treated breasts (1 bilateral) enrolled onto the phase 2 portion of the trial out of 45 originally planned. The trial was closed to accrual because of the coronavirus pandemic and not reopened. Thirty-eight breasts were treated with double-scattering and 3 pencil-beam scanning protons. The median follow-up of the 40 patients is 5.4 years (range, 2.3-8.6 years). There was 1 local recurrence. There was no grade ≥3 acute or late toxicity. At baseline all patients had physician-rated cosmesis good or excellent but at 2 years was excellent in 56%, good in 19%, and fair in 25%. Conclusions: Proton-accelerated partial breast irradiation delivered with a twice-daily fractionation was feasible and associated with very low acute and long-term toxicity. However, the trial did not meet goals for cosmesis outcomes and was closed prematurely. Future study is needed to determine whether pencil-beam scanning protons or different fractionation could improve these outcomes.

Comparing long-term sexual dysfunction across different uterine cancer treatment modalities.

INTRODUCTION: The objective of this study was to assess differences in long-term sexual and menopausal side effects after uterine cancer treatment among treatment modalities. METHODS AND MATERIALS: This is a cross-sectional study that examined women treated for uterine cancer from 2006-2018. Eligible women included those who underwent a hysterectomy/bilateral salpino-oophorectemy alone (HS), with brachytherapy (BT), or with external beam radiation therapy (EBRT). A noncancer cohort of women who underwent a hysterectomy/BSO for benign indications were also identified (non-CA). To compare outcomes, we utilized a shortened form of the female sexual function index (FSFI) and the menopause survey, which consists of 3 subscales: hot flashes, vaginal symptoms, and urinary symptoms. Demographic, comorbidity, and other treatment variables were collected. Survey totals were compared across cohorts using ANOVA tests and logistic regression. RESULTS: A total of 284 women completed the Menopause Survey (Non-CA 64, HS 60, BT 69, EBRT 91); 116 women reported sexual activity in the last 4 weeks and completed the FSFI (NC 32, HS 21, BT 31, EBRT 32). The mean FSFI score for the entire cohort was 11.4 (SD 4.16), which indicates poor sexual function. There was no significant difference between any cohort in the overall FSFI score (p = 0.708) or in any of the FSFI subscales (all p > 0.05). On univariate analysis, BT was associated with fewer menopausal hot flashes and vaginal symptoms compared to the non-CA cohort (p < 0.05), which did not persist on multivariable analysis. CONCLUSION: There was no significant difference in sexual dysfunction or menopausal symptoms in those treated for uterine cancer with or without adjuvant radiation. Most patients reported poor sexual function.

Management and long-term clinical outcomes of patients with stage IVA cervical cancer with bladder involvement.

OBJECTIVE: To describe the long-term outcomes of patients with stage IVA cervical cancer, a rare and deadly disease for which long-term toxicity data are scarce, to guide clinician counseling and survivorship support. METHODS: In a retrospective review of a prospectively maintained database, we identified 76 patients with stage IVA cervical cancer with biopsy- or MRI-proven bladder mucosal involvement who received definitive radiotherapy (external beam radiotherapy [EBRT] alone or EBRT plus brachytherapy) with or without chemotherapy at our institution between 2000 and 2020. We used Kaplan-Meier modeling to estimate recurrence-free survival (RFS) and overall survival (OS) and used proportional hazard modeling to identify clinical variables associated with recurrence or survival. We performed actuarial competing risk modeling for severe late toxicity (grades 3 to 5, occurring >6 months of follow-up) and vesicovaginal fistulae (VVF), censoring for pelvic recurrence and death, and made comparisons between potential predictors using Gray's test and binary logistic regression. RESULTS: The median follow-up time was 76 months (interquartile range 58-91). The median OS duration was 35 months (range, 18-not reached), and the 2- and 5-year OS rates were 53.6% and 40.9%, respectively. OS and RFS did not differ significantly between patients who received EBRT alone (N = 18) or EBRT plus brachytherapy (N = 49). Current smoking was a strong predictor of severe late toxicity, whose incidence was 14% at 2 years and 17% at 10 years. The VVF incidence was 24% at 2 years and 32% at 10 years. CONCLUSION: Patients with stage IVA cervical cancer, even those who receive EBRT alone, can have long-term survival. These patients should be followed closely for late radiation-related toxicity.

Exploratory analysis of the cervix tumoral HPV antigen-specific T-cell repertoire during chemoradiation and after brachytherapy.

BACKGROUND: Chemoradiation (CRT) may modulate the immune milieu as an in-situ vaccine. Rapid dose delivery of brachytherapy has unclear impact on T-cell repertoires. HPV-associated cancers express viral oncoproteins E6/E7, which enable tracking antigen/tumor-specific immunity during CRT. METHODS: Thirteen cervical cancer patients on a multi-institutional prospective protocol from 1/2020-1/2023 underwent standard-of-care CRT with pulsed-dose-rate brachytherapy boost (2 fractions). Cervix swabs at various timepoints underwent multiplex DNA deep sequencing of the TCR-ß/CDR3 region with immunoSEQ. Separately, HPV-responsive T-cell clones were also expanded ex vivo. Statistical analysis was via Mann-Whitney-U. RESULTS: TCR productive clonality, templates, frequency, or rearrangements increased post-brachytherapy in 8 patients. Seven patients had E6/E7-responsive evolution over CRT with increased productive templates (ranges: 1.2-50.2 fold-increase from baseline), frequency (1.2-1.7), rearrangements (1.2-40.2), and clonality (1.2-15.4). Five patients had HPV-responsive clonal expansion post-brachytherapy, without changes in HPV non-responsive clones. Epitope mapping revealed VDJ rearrangements targeting cervical cancer-associated antigens in 5 patients. The only two patients with disease recurrence lacked response in all metrics. A lack of global TCR remodeling correlated with worse recurrence-free survival, p = 0.04. CONCLUSION: CRT and brachytherapy alters the cervical cancer microenvironment to facilitate the expansion of specific T-cell populations, which may contribute to treatment efficacy.

Tumor-resident Lactobacillus iners confer chemoradiation resistance through lactate-induced metabolic rewiring.

Tumor microbiota can produce active metabolites that affect cancer and immune cell signaling, metabolism, and proliferation. Here, we explore tumor and gut microbiome features that affect chemoradiation response in patients with cervical cancer using a combined approach of deep microbiome sequencing, targeted bacterial culture, and in vitro assays. We identify that an obligate L-lactate-producing lactic acid bacterium found in tumors, Lactobacillus iners, is associated with decreased survival in patients, induces chemotherapy and radiation resistance in cervical cancer cells, and leads to metabolic rewiring, or alterations in multiple metabolic pathways, in tumors. Genomically similar L-lactate-producing lactic acid bacteria commensal to other body sites are also significantly associated with survival in colorectal, lung, head and neck, and skin cancers. Our findings demonstrate that lactic acid bacteria in the tumor microenvironment can alter tumor metabolism and lactate signaling pathways, causing therapeutic resistance. Lactic acid bacteria could be promising therapeutic targets across cancer types.

Patient Reported Outcomes for Women Undergoing Definitive Chemoradiation for Gynecologic Cancer: A Prospective Clinical Trial.

PURPOSE: Patients with gynecologic malignancies have high psychosocial and symptom burden. We report data from a prospective trial evaluating patient-reported outcome (PRO) metrics in women undergoing definitive chemoradiation with brachytherapy (BT). METHODS AND MATERIALS: A single-institution prospective trial evaluating outcomes of gynecologic cancer patients undergoing BT. Questionnaires to assess PROs at baseline, post-BT, and 60-day follow-up were collected, using European Organization for Research and Treatment of Cancer-Quality of Life Question-Core 30 and European Organization for Research and Treatment of Cancer-Quality of Life Question-Cervical Cancer Module validated metrics. Higher scores for functional scales/global health and lower scores for symptom items are favorable. European Organization for Research and Treatment of Cancer-Quality of Life Question-Core 30 mean scores were compared with a reference population. When comparing the study population between time points, medians, interquartile range, and nonparametric testing were used. RESULTS: Thirty-three patients were enrolled, and 29 (88%) completed baseline PRO metrics. Mean global health score was worse than the reference population of women with any cancer diagnosis at baseline (41 vs 59, P < .001) and decreased further at follow-up (42 vs 33, P = .005). Compared with the cervical cancer reference, our patients had significantly worse social function (62 vs 83, P = .03), financial toxicity (49 vs 10, P < .001), fatigue (49 vs 34, P = .04), nausea/vomiting (26 vs 9, P = .001), and appetite loss (36 vs 16, P = .004).The majority of patients described depression (53%), feeling less attractive (64%), life interference (66%), and/or worry (69%). At baseline, higher global health scores were associated with improved physical functioning (R20.58, P < .001), social functioning (R20.56, P < .001), and body image (R20.40, P < .001); lower scores with more symptom burden (R20.71, P < .001), financial toxicity (R20.50, P < .001), and/or sexual worry (R20.25, P = .001). CONCLUSIONS: Patients with cervical cancer have significant symptom burden and psychosocial toxicity, contributing to decreased quality of life. These data highlight the need for improved support throughout treatment for this high-risk population.

Acute and long-term toxicity of whole pelvis proton radiation therapy for definitive or adjuvant management of gynecologic cancers.

OBJECTIVE: To characterize long-term toxicity and disease outcomes with whole pelvis (WP) pencil beam scanning proton radiation therapy (PBS PRT) for gynecologic malignancies. METHODS: We reviewed 23 patients treated from 2013 to 2019 with WP PBS PRT for endometrial, cervical, and vaginal cancer. We report acute and late Grade (G)2+ toxicities, graded by Common Terminology Criteria for Adverse Events, Version 5. Disease outcomes were assessed by Kaplan-Meier method. RESULTS: Median age was 59 years. Median follow up was 4.8 years. 12 (52.2%) had uterine cancer, 10 (43.5%) cervical, 1 (4.3%) vaginal. 20 (86.9%) were treated post-hysterectomy. 22 (95.7%) received chemotherapy, 12 concurrently (52.2%). The median PBS PRT dose was 50.4GyRBE (range, 45-62.5). 8 (34.8% had para-aortic/extended fields. 10 (43.5%) received brachytherapy boost. Median follow up was 4.8 years. 5-year actuarial local control was 95.2%, regional control 90.9%, distant control 74.7%, both disease control and progression-free survival 71.2%. Overall survival was 91.3%. In the acute period, 2 patients (8.7%) had G2 genitourinary (GU) toxicity, 6 (26.1%) had gastrointestinal (GI) G2-3 toxicity, 17 (73.9%) had G2-4 hematologic (H) toxicity. In the late period, 3 (13.0%) had G2 GU toxicity, 1 (4.3%) had G2 GI toxicity, 2 (8.7%) had G2-3H toxicity. The mean small bowel V15Gy was 213.4 cc. Mean large bowel V15 Gy was 131.9 cc. CONCLUSIONS: WP PBS PRT for gynecologic malignancies delivers favorable locoregional control. Rates of GU and GI toxicity are low. Acute hematologic toxicity was most common, which may be related to the large proportion of patients receiving chemotherapy.

Circulating neutrophils and tumor-associated myeloid cells function as a powerful biomarker for response to chemoradiation in locally advanced cervical cancer.

Purpose: The immune system's role in mediating the cytotoxic effects of chemoradiotherapy remains not completely understood. The integration of immunotherapies into treatment will require insight into features and timing of the immune microenvironment associated with treatment response. Here, we investigated the role of circulating neutrophils and tumor-associated myeloid cells (TSAMs) as potential agents and biomarkers for disease-related outcomes in locally advanced cervical cancer (LACC). Material and Methods: Hematologic parameters for two LACC patient cohorts, a retrospective clinical and a prospective translational cohort, were obtained at baseline, weekly during chemoradiotherapy for the retrospective cohort, biweekly during chemoradiotherapy for the prospective cohort, and at the first follow-up visit for both cohorts (mean 14.7 weeks, range 8.1-25.1 weeks for the prospective cohort and 5.3 weeks with a range of 2.7-9.0 weeks for the retrospective cohort). In both cohorts, baseline as well as mean and lowest on-treatment values for platelets, hemoglobin, absolute neutrophil count (ANC), and absolute lymphocyte count (ALC) were analyzed for correlations with disease-related outcomes. In the prospective cohort, circulating myeloid cells were isolated from peripheral blood mononuclear cells (PBMCs), and TSAMs were isolated from tumor tissue via a novel serial cytobrush sampling assay. The samples were analyzed by flow cytometry. Results: In both cohorts, the only hematologic parameter significantly associated with survival was elevated on-treatment mean ANC (mANC), which was associated with lower local failure-free and overall survival rates in the retrospective and prospective cohorts, respectively. mANC was not associated with a difference in distant metastases. CD11b+CD11c- TSAMs, which act as a surrogate marker for intratumoral neutrophils, steadily decreased during the course of chemoRT and nadier'd at week 5 of treatment. Conversely, circulating myeloid cells identified from PBMCs steadily increased through week 5 of treatment. Regression analysis confirmed an inverse relationship between circulating myeloid cells and TSAMs at this time point. Conclusions: These findings identify on-treatment mean neutrophil count as a predictor of disease-related outcomes, suggest that neutrophils contribute to chemoradiation treatment resistance, and demonstrate the importance of techniques to measure intratumoral immune activity.

GEC-ESTRO (ACROP)-ABS-CBG Consensus Brachytherapy Target Definition Guidelines for Recurrent Endometrial and Cervical Tumors in the Vagina.

PURPOSE: Representatives from the Gynecologic Groupe European de Curietherapie-European Society for Radiation Therapy and Oncology (GYN GEC-ESTRO), the American Brachytherapy Society (ABS), and the Canadian Brachytherapy Group (CBG) met to develop international consensus recommendations for target definitions for image-guided adaptive brachytherapy for vaginal recurrences of endometrial or cervical cancer. METHODS AND MATERIALS: Seventeen radiation oncologists and 2 medical physicists participated. Before an in-person meeting each participant anonymously contoured 3 recurrent endometrial/cervical cancer cases. Participants contoured the residual gross primary tumor volume (GTV-Tres), a high-risk clinical target volume (CTV-THR), and an intermediate-risk clinical target volume (CTV-TIR), on T2-weighted magnetic resonance images (MRIs). All contours were drawn using Falcon EduCase. Contours were reviewed at an in-person meeting during which a consensus document was created defining agreed-upon target definitions (Trial 1). After establishing these definitions, the group was sent one of the cases again (recurrent cervical cancer vaginal recurrence) and asked to contour the targets again (Trial 2). The Computerized Environment for Radiation Research (CERR) software (The Mathworks, Natwick, MA) was used to analyze the contours. Kappa statistics were generated to assess level of agreement between contours. A conformity index (CI), defined as the ratio between the intersection and union volume of a given pair of contours, was calculated. A simultaneous truth and performance level estimation (STAPLE) contour was created for the CTV-THR and CTV-TIR for the postmeeting case. RESULTS: Consensus definitions for GTV-Tres, CTV-THR, and CTV-TIR were established. Kappa statistics (Trial 1/Trial 2) for GTV-Tres, CTV-THR, and CTV-TIR were 0.536/0.583, 0.575/0.743 and 0.522/0.707. Kappa statistics for Trial 2 for the CTV-THR and CTV-TIR showed "substantial" agreement while the GTV-Tres remained at moderate agreement. CONCLUSIONS: This consensus provides recommendations to facilitate future collaborations for MRI-guided adaptive brachytherapy target definitions in endometrial/cervical vaginal recurrences.

[18F]FluorThanatrace ([18F]FTT) PET Imaging of PARP-Inhibitor Drug-Target Engagement as a Biomarker of Response in Ovarian Cancer, a Pilot Study.

PURPOSE: PARP inhibitors have become the standard-of-care treatment for homologous recombination deficient (HRD) high-grade serous ovarian cancer (HGSOC). However, not all HRD tumors respond to PARPi. Biomarkers to predict response are needed. [18F]FluorThanatrace ([18F]FTT) is a PARPi-analog PET radiotracer that noninvasively measures PARP-1 expression. Herein, we evaluate [18F]FTT as a biomarker to predict response to PARPi in patient-derived xenograft (PDX) models and subjects with HRD HGSOC. EXPERIMENTAL DESIGN: In PDX models, [18F]FTT-PET was performed before and after PARPi (olaparib), ataxia-telangiectasia inhibitor (ATRi), or both (PARPi-ATRi). Changes in [18F]FTT were correlated with tumor volume changes. Subjects were imaged with [18F]FTT-PET at baseline and after ∼1 week of PARPi. Changes in [18F]FTT-PET uptake were compared with changes in tumor size (RECISTv1.1), CA-125, and progression-free survival (PFS). RESULTS: A decrease in [18F]FTT tumor uptake after PARPi correlated with response to PARPi, or PARPi-ATRi treatment in PARPi-resistant PDX models (r = 0.77-0.81). In subjects (n = 11), percent difference in [18F]FTT-PET after ∼7 days of PARPi compared with baseline correlated with best RECIST response (P = 0.01), best CA-125 response (P = 0.033), and PFS (P = 0.027). All subjects with >50% reduction in [18F]FTT uptake had >6-month PFS and >50% reduction in CA-125. Utilizing only baseline [18F]FTT uptake did not predict such responses. CONCLUSIONS: The decline in [18F]FTT uptake shortly after PARPi initiation provides a measure of drug-target engagement and shows promise as a biomarker to guide PARPi therapies in this pilot study. These results support additional preclinical mechanistic and clinical studies in subjects receiving PARPi ± combination therapy. See related commentary by Liu and Zamarin, p. 1384.

Quality Assurance in Clinical Trials Requiring Radiation Therapy in Sub-Saharan Africa.

PURPOSE: Given the increasing availability of radiation therapy in sub-Saharan Africa, clinical trials that include radiation therapy are likely to grow. Ensuring appropriate delivery of radiation therapy through rigorous quality assurance is an important component of clinical trial execution. We reviewed the process for credentialing radiation therapy sites and radiation therapy quality assurance through the Imaging and Radiation Oncology Core (IROC) Houston Quality Assurance Center for AIDS Malignancy Consortium (AMC)-081, a multicenter study of cisplatin and radiation therapy for women with locally advanced cervical cancer living with HIV, conducted by the AIDS Malignancy Consortium at 2 sites in South Africa and Zimbabwe. METHODS AND MATERIALS: Women living with HIV with newly diagnosed stage IB2, IIA (>4 cm), IIB-IVA cervical carcinoma (per the 2009 International Federation of Gynecology and Obstetrics [FIGO] staging classifications) were enrolled in AMC-081. They received 3-dimensional conformal external beam radiation therapy (EBRT) to the pelvis (41.4-45 Gy) using a linear accelerator, high-dose-rate brachytherapy (6-9 Gy to point A with each fraction and up to 4 fractions), and concurrent weekly cisplatin (40 mg/m2). IROC reviewed EBRT and brachytherapy quality assurance records after treatment. RESULTS: All of the 38 women enrolled in AMC-081 received ±5% of the protocol-specified prescribed dose of EBRT. Geometry of brachytherapy applicator placement was scored as per protocol in all implants. Doses to points A and B, International Commission on Radiation Units and Measurements (ICRU) bladder, or ICRU rectum required correction by IROC in >50% of the implants. In the final evaluation, 58% of participants (n = 22) were treated per protocol, 40% (n = 15) had minor protocol deviations, and 3% (n = 1) had major protocol deviations. No records were received within 60 days of treatment completion as requested in the protocol. CONCLUSIONS: Major radiation therapy deviations were low, but timely submission of radiation therapy data did not occur. Future studies, especially those that include specialized radiation therapy techniques such as stereotactic or intensity-modulated radiation therapy, will require pathways to ensure timely and adequate quality assurance.

Metagenomes of rectal swabs in larger, advanced stage cervical cancers have enhanced mucus degrading functionalities and distinct taxonomic structure.

BACKGROUND: Gut microbiome community composition differs between cervical cancer (CC) patients and healthy controls, and increased gut diversity is associated with improved outcomes after treatment. We proposed that functions of specific microbial species adjoining the mucus layer may directly impact the biology of CC. METHOD: Metagenomes of rectal swabs in 41 CC patients were examined by whole-genome shotgun sequencing to link taxonomic structures, molecular functions, and metabolic pathway to patient's clinical characteristics. RESULTS: Significant association of molecular functions encoded by the metagenomes was found with initial tumor size and stage. Profiling of the molecular function abundances and their distributions identified 2 microbial communities co-existing in each metagenome but having distinct metabolism and taxonomic structures. Community A (Clostridia and Proteobacteria predominant) was characterized by high activity of pathways involved in stress response, mucus glycan degradation and utilization of degradation byproducts. This community was prevalent in patients with larger, advanced stage tumors. Conversely, community B (Bacteroidia predominant) was characterized by fast growth, active oxidative phosphorylation, and production of vitamins. This community was prevalent in patients with smaller, early-stage tumors. CONCLUSIONS: In this study, enrichment of mucus degrading microbial communities in rectal metagenomes of CC patients was associated with larger, more advanced stage tumors.

Perspectives of Zambian Clinical Oncology Trainees in the MD Anderson and Zambia Virtual Clinical Research Training Program (MOZART).

BACKGROUND: African countries are underrepresented in cancer research, partly because of a lack of structured curricula on clinical research during medical education. To address this need, the MD Anderson and Zambia Virtual Clinical Research Training Program (MOZART) was developed jointly by MD Anderson Cancer Center (MDA) and the Cancer Diseases Hospital in Zambia (CDH) for Zambian clinical oncology trainees. We explored participant perspectives to provide insight for implementation of similar efforts. MATERIALS AND METHODS: The MD Anderson and Zambia Virtual Clinical Research Training Program consisted of weekly virtual lectures and support of Zambian-led research protocols through longitudinal mentorship groups that included CDH faculty and MDA peer and faculty mentors. Participants were contacted via email to take part in semi-structured interviews, which were conducted via teleconference and audio-recorded, transcribed, and coded. Emergent themes were extracted and are presented with representative verbatim quotations. RESULTS: Thirteen of the 14 (93%) trainees were interviewed. Emergent themes included (1) participants having diverse educational backgrounds but limited exposure to clinical research, (2) importance of cancer research specific to a resource-constrained setting, (3) complementary roles of peer mentors and local and international faculty mentors, (4) positive impact on clinical research skills but importance of a longitudinal program and early exposure to clinical research, and (5) challenges with executing research protocols. CONCLUSION: To our knowledge, this is the first qualitative study of African clinical oncology trainees participating in a virtual clinical research training program. The lessons learned from semi-structured interviews with participants in MOZART provided valuable insights that can inform the development of similar clinical research training efforts and scale-up.