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Complicating factors such as time pressures, anatomic variants in the spine, and similarities in adjacent vertebrae are associated with incorrect level treatments of the spine. The purpose of this work was to mitigate such challenges by fully automating the treatment planning process for diagnostic and simulation computed tomography (CT) scans.Vertebral bodies are labeled on CT scans of any length using 2 intendent deep-learning models-mirroring 2 different experts labeling the spine. Then, a U-Net++ architecture was trained, validated, and tested to contour each vertebra (n = 220 CT scans). Features from the CT and auto-contours were input into a random forest classifier to predict whether vertebrae were correctly labeled. This classifier was trained using auto-contours from cone beam computed tomography, positron emission tomography/CT, simulation CT, and diagnostic CT images (n = 56 CT scans, 751 contours). Auto-plans were generated via scripting. Each model was combined into a framework to make a fully automated clinical tool. A retrospective planning study was conducted in which 3 radiation oncologists scored auto-plan quality on an unseen patient cohort (n = 60) on a 5-point scale. CT scans varied in scan length, presence of surgical implants, imaging protocol, and metastatic burden.The results showed that the uniquely designed convolutional neural networks accurately labeled and segmented vertebral bodies C1-L5 regardless of imaging protocol or metastatic burden. Mean dice-similarity coefficient was 85.0% (cervical), 90.3% (thoracic), and 93.7% (lumbar). The random forest classifier predicted mislabeling across various CT scan types with an area under the curve of 0.82. All contouring and labeling errors within treatment regions (11 of 11), including errors from patient plans with atypical anatomy (eg, T13, L6) were detected. Radiation oncologists scored 98% of simulation CT-based plans and 92% of diagnostic CT-based plans as clinically acceptable or needing minor edits for patients with typical anatomy. On average, end-to-end treatment planning time of the clinical tool was less than 8 minutes.This novel method to automatically verify, contour, and plan palliative spine treatments is efficient and effective across various CT scan types. Furthermore, it is the first to create a clinical tool that can automatically verify vertebral level in CT images.

Patients with localized squamous cell carcinoma of the anus (SCCA) who experience treatment toxicity or recurrences have few therapeutic options. Investigation into the microbiome's influence on treatment toxicity and its potential use as a predictive biomarker could improve these patients' outcomes. Our study presents the first longitudinal characterization of the SCCA tumor microbiome and its associations with treatment-related toxicities.This prospective cohort study included patients with nonmetastatic SCCA receiving standard-of-care chemoradiation therapy. Anorectal swabs of the tumor site were collected before, during, and after treatment. Patient-reported quality-of-life metrics were collected at similar time points. 16S rRNA gene sequencing was used to perform diversity and taxonomic characterization of the SCCA microbiome. Wilcoxon signed-rank tests were used to compare microbial diversity and abundance over time. Wilcoxon rank-sum tests were used to compare microbial profiles of high and low toxicity groups.Twenty-two patients with SCCA were included in this study with a median age of 58.5 years (range, 39-77 years), and 18 (82%) were women. Alpha diversity remained relatively stable throughout chemoradiation therapy except for decreases in the Observed Features (P = .03) index at week 5 relative to baseline. Tumor microbial compositions changed significantly by the end of treatment (P = .03). Differential enrichment of bacteria at specific time points occurred during treatment, including the enrichment of Clostridia at follow-up (vs week 5, q = 0.019) and Corynebacterium at week 5 (vs baseline, q = 0.015; vs follow-up, q = 0.022). Patients experiencing high toxicity at week 5 had higher relative counts of Clostridia, Actinobacteria, and Clostridiales at baseline (P = .03 for all).The tumor microbiome changes during and after chemoradiation therapy, and patient-reported toxicity levels are associated with patients' microbial profiles. Further studies into these microbial characterizations and toxicity associations will elucidate the tumor microbiome's role in predicting treatment-related outcomes for patients with SCCA.

Human papillomavirus (HPV) infection causes 600,000 new cancers worldwide each year. HPV-related cancers express the oncogenic proteins E6 and E7, which could serve as tumor-specific antigens. It is not known whether immunity to E6 and E7 evolves during chemoradiotherapy or affects survival. Using T cells from 2 HPV16+ patients, we conducted functional T-cell assays to identify candidate HPV-specific T cells and common T-cell receptor motifs, which we then analyzed across 86 patients with HPV-related cancers. The HPV-specific clones and E7-related T-cell receptor motifs expanded in the tumor microenvironment over the course of treatment, whereas non–HPV-specific T cells did not. In HPV16+ patients, improved recurrence-free survival was associated with HPV-responsive T-cell expansion during chemoradiotherapy.

Supplementary DataSupplemental Figures and Legends

Supplemental Table LegendsSupplemental Table Legends

Supplemental TablesTables S1-S13

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Metadata of mice in the study

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Human papillomavirus (HPV) infection causes 600,000 new cancers worldwide each year. HPV-related cancers express the oncogenic proteins E6 and E7, which could serve as tumor-specific antigens. It is not known whether immunity to E6 and E7 evolves during chemoradiotherapy or affects survival. Using T cells from 2 HPV16+ patients, we conducted functional T-cell assays to identify candidate HPV-specific T cells and common T-cell receptor motifs, which we then analyzed across 86 patients with HPV-related cancers. The HPV-specific clones and E7-related T-cell receptor motifs expanded in the tumor microenvironment over the course of treatment, whereas non–HPV-specific T cells did not. In HPV16+ patients, improved recurrence-free survival was associated with HPV-responsive T-cell expansion during chemoradiotherapy.

Figure S5. Representative images from continuous longitudinal H&E sections of the proximal duodenum (Proximal) through the first part of the jejunum (distal), running left to right, then top to bottom. Each new row is a continuation of the end of the previous row. Portions of the villi blunting and crypt hypertrophy were observed in 2/5 mice in the VEH+RT group (middle, red blocks), but not in the VEH or FG+RT groups. These data provide an overview of a large continuous section of the intestine, which is important since only a portion of the GI tract is radiating in our focused fields. Scale bars=100 microns

When pancreatic cancer cannot be removed surgically, patients frequently experience morbidity and death from progression of their primary tumor. Radiation therapy (RT) cannot yet substitute for an operation because radiation causes fatal bleeding and ulceration of the nearby stomach and intestines before achieving tumor control. There are no FDA-approved medications that prevent or reduce radiation-induced gastrointestinal injury. Here, we overcome this fundamental problem of anatomy and biology with the use of the oral EGLN inhibitor FG-4592, which selectively protects the intestinal tract from radiation toxicity without protecting tumors. A total of 70 KPC mice with autochthonous pancreatic tumors received oral FG-4592 or vehicle control ± ablative RT to a cumulative 75 Gy administered in 15 daily fractions to a limited tumor field. Although ablative RT reduced complications from local tumor progression, fatal gastrointestinal bleeding was observed in 56% of mice that received high-dose RT with vehicle control. However, radiation-induced bleeding was completely ameliorated in mice that received high-dose RT with FG-4592 (0% bleeding, P < 0.0001 compared with vehicle). Furthermore, FG-4592 reduced epithelial apoptosis by half (P = 0.002) and increased intestinal microvessel density by 80% compared with vehicle controls. EGLN inhibition did not stimulate cancer growth, as treatment with FG-4592 alone, or overexpression of HIF2 within KPC tumors independently improved survival. Thus, we provide a proof of concept for the selective protection of the intestinal tract by the EGLN inhibition to enable ablative doses of cytotoxic therapy in unresectable pancreatic cancer by reducing untoward morbidity and death from radiation-induced gastrointestinal bleeding.Significance:Selective protection of the intestinal tract by EGLN inhibition enables potentially definitive doses of radiation therapy. This might allow radiation to be a surgical surrogate for unresectable pancreatic cancer.

Table S1. Distribution of Tumor and Treatment Characteristics for All Enrolled Animals by Treatment Group

PDF file - 981KB, Representative Immunohistochemistry for CHD7 Expression in Primary Tumor Tissue (S1). Network Analysis via MetaCore ExPlain Process Network Analysis for genes involved in CHK1, CDC25A, AURKB, PLK1, HUS1 pathway (S2). CHD7 Knockdown Causes Gemcitabine Sensitization (S3). Mice with Xenograft Tumors Showed No Significant Difference in Body Weight (S4). CHD7 Knockdown Effect on Cell Cycle (S5). Gemcitabine Does Not Significantly Change CHD7 Protein Levels in Cells (S6).

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XLS file - 675KB, Full Results of Primary Gemcitabine Sensitivity Screen (S1). Known DNA Damage Response Genes Identified as Hits in Gemcitabine Sensitivity Screen (S2). Dysregulation, Differential Expression, and Literature RNAi Cross-Reference for Known DDR Genes and Select Hits (S3). Selected Top 15% of Gemcitabine Sensitivity Genes Tested on Secondary Screen (S4).

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with poor outcomes with current therapies. Gemcitabine is the primary adjuvant drug used clinically, but its effectiveness is limited. In this study, our objective was to use a rationale-driven approach to identify novel biomarkers for outcome in patients with early-stage resected PDAC treated with adjuvant gemcitabine. Using a synthetic lethal screen in human PDAC cells, we identified 93 genes, including 55 genes linked to DNA damage responses (DDR), that demonstrated gemcitabine sensitization when silenced, including CHD7, which functions in chromatin remodeling. CHD7 depletion sensitized PDAC cells to gemcitabine and delayed their growth in tumor xenografts. Moreover, CHD7 silencing impaired ATR-dependent phosphorylation of CHK1 and increased DNA damage induced by gemcitabine. CHD7 was dysregulated, ranking above the 90th percentile in differential expression in a panel of PDAC clinical specimens, highlighting its potential as a biomarker. Immunohistochemical analysis of specimens from 59 patients with resected PDAC receiving adjuvant gemcitabine revealed that low CHD7 expression was associated with increased recurrence-free survival (RFS) and overall survival (OS), in univariate and multivariate analyses. Notably, CHD7 expression was not associated with RFS or OS for patients not receiving gemcitabine. Thus, low CHD7 expression was correlated selectively with gemcitabine sensitivity in this patient population. These results supported our rationale-driven strategy to exploit dysregulated DDR pathways in PDAC to identify genetic determinants of gemcitabine sensitivity, identifying CHD7 as a novel biomarker candidate to evaluate further for individualizing PDAC treatment. Cancer Res; 74(10); 2677–87. ©2014 AACR.

BackgroundSquamous cell carcinoma of the anus (SCCA) is a rare gastrointestinal cancer. Factors associated with progression of HPV infection to anal dysplasia and cancer are unclear and screening guidelines and approaches for anal dysplasia are less clear than for cervical dysplasia. One potential contributing factor is the anorectal microbiome. In this study, we aimed to identify differences in anal microbiome composition in the settings of HPV infection, anal dysplasia, and anal cancer in this rare disease.MethodsPatients were enrolled in two prospective studies. Patients with anal dysplasia were part of a cross-sectional cohort that enrolled women with high-grade lower genital tract dysplasia. Anorectal tumor swabs were prospectively collected from patients with biopsy-confirmed locally advanced SCCA prior to receiving standard-of-care chemoradiotherapy (CRT). Patients with high-grade lower genital tract dysplasia without anal dysplasia were considered high-risk (HR Normal). 16S V4 rRNA Microbiome sequencing was performed for anal swabs. Alpha and Beta Diversity and composition were compared for HR Normal, anal dysplasia, and anal cancer.Results60 patients with high-grade lower genital tract dysplasia were initially enrolled. Seven patients had concurrent anal dysplasia and 44 patients were considered HR Normal. Anorectal swabs from 21 patients with localized SCCA were included, sequenced, and analyzed in the study. Analysis of weighted and unweighted UniFrac distances demonstrated significant differences in microbial community composition between anal cancer and HR normal (p=0.018). LEfSe identified that all three groups exhibited differential enrichment of specific taxa. Peptoniphilus (p=0.028), Fusobacteria (p=0.0295), Porphyromonas (p=0.034), and Prevotella (p=0.029) were enriched in anal cancer specimens when compared to HR normal.ConclusionAlthough alpha diversity was similar between HR Normal, dysplasia and cancer patients, composition differed significantly between the three groups. Increased anorectal Peptoniphilus, Fusobacteria, Porphyromonas, and Prevotella abundance were associated with anal cancer. These organisms have been reported in various gastrointestinal cancers with roles in facilitating the proinflammatory microenvironment and neoplasia progression. Future work should investigate a potential role of microbiome analysis in screening for anal dysplasia and investigation into potential mechanisms of how these microbial imbalances influence the immune system and anal carcinogenesis.

PURPOSE In an effort to promote cost-conscious, high-quality, and patient-centered care in the palliative radiation of painful bone metastases, the National Quality Forum (NQF) formed measure 1822 in 2012, which recommends the use of one of the four dose-fractionation schemes (30 Gy in 10 fractions, 24 Gy in 6 fractions, 20 Gy in 5 fractions, or 8 Gy in a single fraction). We investigated whether a custom electronic health record (EHR) alert system improved quality measure compliance among 88 physicians at a large academic center and institutional network. METHODS In March 2018, a multiphase alert system was embedded in a custom web-based EHR. Prior to a course of palliative bone radiation, the alert system notified the user of NQF 1822 recommendations and, once prescription was completed, either affirmed compliance or advised a change in treatment schedule. Rates of compliance were evaluated before and after implementation of alert system. RESULTS Of 2,399 treatment courses, 86.5% were compliant with NQF 1822 recommendations. There was no difference in rates of NQF 1822 compliance before or after implementation of the custom EHR alert (86.0% before March 2018 v 86.9% during and after March 2018, P = .551). CONCLUSION There was no change in rates of compliance following implementation of a custom EHR alert system designed to make treatment recommendations based on national quality measure guidelines. To be of most benefit, future palliative bone metastasis decision aids should leverage peer review, target a clear practice deficiency, center upon high-quality practice guidelines, and allow flexibility to reflect the diversity of clinical scenarios.

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.

We evaluated the association of disease outcome with T cell immune-related characteristics and T cell receptor (TCR) repertoire in malignant ascites from patients with high-grade epithelial ovarian cancer. Ascitic fluid samples were collected from 47 high-grade epithelial ovarian cancer patients and analyzed using flow cytometry and TCR sequencing to characterize the complementarity determining region 3 TCR β-chain. TCR functions were analyzed using the McPAS-TCR and VDJ databases. TCR clustering was implemented using Grouping of Lymphocyte Interactions by Paratope Hotspots software. Patients with poor prognosis had ascites characterized by an increased ratio of CD8+ T cells to regulatory T cells, which correlated with an increased productive frequency of the top 100 clones and decreased productive entropy. TCRs enriched in patients with an excellent or good prognosis were more likely to recognize cancer antigens and contained more TCR reads predicted to recognize epithelial ovarian cancer antigens. In addition, a TCR motif that is predicted to bind the TP53 neoantigen was identified, and this motif was enriched in patients with an excellent or good prognosis. Ascitic fluid in high-grade epithelial ovarian cancer patients with an excellent or good prognosis is enriched with TCRs that may recognize ovarian cancer-specific neoantigens, including mutated TP53 and TEAD1. These results suggest that an effective antigen-specific immune response in ascites is vital for a good outcome in high-grade epithelial ovarian cancer.

Background: There exists wide practice variability in palliative treatment schedules for bone metastases. In an effort to reduce variation and promote high-quality, cost-conscious care, the National Quality Forum (NQF) endorsed measure 1822 in 2012. This measure recommends the use of 30 Gy in 10 fractions, 24 Gy in 6 fractions, 20 Gy in 5 fractions, or 8 Gy in a single fraction for palliative radiation for bone metastases. We report on longitudinal compliance with this measure. Methods: Using the National Cancer Database, patients with metastatic thoracic non–small cell lung cancer diagnosed between 2004 and 2016 who received radiation therapy for bony sites of metastatic disease were identified. Treatment courses fitting 1 of the 4 recommended schedules under NQF 1822 were coded as compliant. Rates of compliance by patient, tumor, and treatment characteristics were analyzed. Results: A total of 42,685 patients met the criteria for inclusion. Among all patients, 60.2% of treatment courses were compliant according to NQF 1822. Compliance increased over time and was highest for treatments to the extremity (69.8%), lowest for treatments to the skull or head (48.8%), and higher for academic practice (67.1%) compared with community (56.0%) or integrated network facilities (61.2%). On multivariable analysis, predictors of NQF 1822 compliance included year of diagnosis after 2011, treatment to an extremity, or treatment at an academic facility. Of noncompliant treatment courses, extended fractionation (≥11 fractions) occurred in 62.6% and was more common before 2012, in community practice, and for treatments of the skull or head. Conclusions: Among patients treated for metastatic non–small cell lung cancer, compliance with NQF 1822 increased over time. Although extended fractionation constituted a majority of noncompliant treatment courses, a substantial proportion also involved shorter courses.

Highlights • The microbiome of HPV+ oropharynx cancer exhibits reduced alpha diversity during radiotherapy. • The baseline tumor bacterial profiles of smokers vs. non-smokers are inherently different. • Eark High baseline alpha diversity may predict early response to radiation and should be investigated. • Alteration of the tumor microbiome composition occurs as early as in the first week of radiotherapy., Purpose To describe the baseline and serial tumor microbiome in HPV-associated oropharynx cancer (OPC) over the course of radiotherapy (RT). Methods Patients with newly diagnosed HPV-associated OPC treated with definitive radiotherapy +/− concurrent chemotherapy were enrolled in this prospective study. Using 16S rRNA gene sequencing, dynamic changes in the tumor site microbiome during RT were investigated. Surface tumor samples were obtained before RT and at week 1, 3 and 5 of RT. Radiological primary tumor response at mid-treatment was categorized as complete (CR) or partial (PR). Results Ten patients were enrolled, but 9 patients were included in the final analysis. Mean age was 62 years (range: 51–71). As per AJCC 8th Ed, 56%, 22% and 22% of patients had stage I, II and III, respectively. At 4-weeks, 6 patients had CR and 3 patients had PR; at follow-up imaging post treatment, all patients had CR. The baseline diversity of the tumoral versus buccal microbiome was not statistically different. For the entire cohort, alpha diversity was significantly decreased over the course of treatment (p = 0.04). There was a significant alteration in the bacterial community within the first week of radiation. Baseline tumor alpha diversity of patients with CR was significantly higher than those with PR (p = 0.03). While patients with CR had significant reduction in diversity over the course of radiation (p = 0.01), the diversity remained unchanged in patients with PR. Patients with history of smoking had significantly increased abundance of Kingella (0.05) and lower abundance of Stomatobaculum (p = 0.03) compared to never smokers. Conclusions The tumor microbiome of HPV-associated OPC exhibits reduced alpha diversity and altered taxa abundance over the course of radiotherapy. The baseline bacterial profiles of smokers vs. non-smokers were inherently different. Baseline tumor alpha diversity of patients with CR was higher than patients with PR, suggesting that the microbiome deserves further investigation as a biomarker of radiation response.

IntroductionWe characterized the cervical 16S rDNA microbiome of patients in Botswana with high-grade cervical dysplasia and locally advanced cervical cancer.MethodsThis prospective study included 31 patients: 21 with dysplasia and 10 with cancer. The Shannon diversity index was used to evaluate alpha (intra-sample) diversity, while the UniFrac (weighted and unweighted) and Bray–Curtis distances were employed to evaluate beta (inter-sample) diversity. The relative abundance of microbial taxa was compared among samples using linear discriminant analysis effect size.ResultsAlpha diversity was significantly higher in patients with cervical cancer than in patients with cervical dysplasia (PLachnospira bacteria (in the Clostridia class) were particularly enriched among cervical dysplasia patients, while Proteobacteria (members of the Firmicutes phyla and the Comamonadaceae family) were enriched in patients with cervical cancer.DiscussionThe results of our study suggest that differences exist in the diversity and composition of the cervical microbiota between patients with cervical dysplasia and patients with cervical cancer in Botswana. Additional studies are warranted to validate these findings and elucidate their clinical significance among women living in sub-Saharan Africa, as well as other regions of the world.

SUMMARYThis study identifies a novel pathotype of cervical cancer-associated Lactobacillus iners (L. iners) that results in chemoradiation resistance in vitro and is associated with poor patient survival. Cervical cancer affects over half a million women a year around the world. Treatment for women with locally advanced cancer is delivered with definitive chemoradiation (CRT) but is curative for only 60% of patients. There are few validated molecular markers to identify patients who will respond poorly to treatment. Tumor microbiome features are associated with treatment resistance in patients with colon and pancreatic cancers, and thus we investigated their role in the response of cervical cancer to therapy. We identified a strong association between poor clinical response to CRT and tumors dominated by L. iners. Cancer-associated L. iners promoted in vitro resistance of cervical cancer cells and modified the local tumor immunologic microenvironment, while non-cancer-associated L. iners did not. Assembly of genomes from cancer-derived L. iners also demonstrated pathogenic, metabolic, and immune functions not found in healthy patients.

We compared the magnitude of changes in bone mineral density (BMD), within and outside the radiation field, among women who received pelvic radiation therapy (RT) with or without chemotherapy for cervical cancer.In this secondary analysis of a prospective study, we analyzed serial computed tomography scans and dual-energy x-ray absorptiometry scans from 78 patients who received definitive RT or chemoradiation therapy (CRT) for cervical cancer at a single institution from 2008 to 2015. BMD values at L1, L2, L3, and L4 were measured. We compared changes in BMD within the radiation field (ie, at L4) with those outside the field (ie, at L1). Linear mixed models were also used to examine the effect of RT on changes in BMD over time and covariate adjustment.The median age of the 78 patients was 45.5 years (range, 23-88 years); all received RT and 76 (97%) received concurrent CRT. Treatment was associated with significant declines in BMD in all 4 lumbar vertebral bodies over time (P.05), with nadir at 3 months for L4 and at 1 year for L1. Pairwise comparisons at 3 months and 2 years after treatment indicated that BMD in L4 (within the RT field) had improved (P = .037), but BMD in L1 (outside the RT field) was no different at 3 months and 2 years.Significant BMD declines were observed in all lumbar vertebral bodies immediately after RT. However, in-field vertebral bodies reached nadir BMD earlier than those located outside the RT field. Our results suggest that treatment and patient-related factors other than RT may contribute to declines in BMD after treatment for cervical cancer. Routine bone density screening and post-RT therapy with hormones may be beneficial for selected patients who receive CRT for cervical cancer.

In multiple anatomic sites, patients with cancers associated with the Human Papillomavirus (HPV) experience better locoregional control and overall survival after radiotherapy and/or chemoradiotherapy than patients with HPV-negative cancers. These improved outcomes suggest that relatively unique biological features in HPV-positive cancers may increase sensitivity to DNA damaging agents as well as an impaired DNA damage response. This review will address potential biological mechanisms driving this increased sensitivity of HPV-positive cancer to radiation and/or chemotherapy. This review will discuss the clinical and preclinical observations that support the intrinsic radiosensitivity and/or chemosensitivity of HPV-positive cancers. Furthermore, this review will highlight the molecular mechanisms for increased radiation sensitivity using the classical "4 Rs" of radiobiology: repair, reassortment, repopulation, and reoxygenation. First, HPV-positive cancers have increased DNA damage due to increased oxidative stress and impaired DNA damage repair due to the altered activity TP53, p16, TIP60, and other repair proteins. Second, irradiated HPV-positive cancer cells display increased G2/M arrest leading to reassortment of cancer cells in more radiosensitive phases of the cell cycle. In addition, HPV-positive cancers have less radioresistant cancer stem cell subpopulations that may limit their repopulation during radiotherapy. Finally, HPV-positive cancers may also have less hypoxic tumor microenvironments that make these cancers more sensitive to radiation than HPV-negative cells. We will also discuss extrinsic immune and microenvironmental factors enriched in HPV-positive cancers that facilities responses to radiation. Therefore, these potential biological mechanisms may underpin the improved clinical outcomes often observed in these virally induced cancers.

Purpose Women remain underrepresented at all levels within the field of radiation oncology. We sought to study current female residents’ experiences and concerns to inform interventions to promote gender equity. Furthermore, we evaluated interest in a professional society specifically for women radiation oncologists. Methods and Materials An anonymous 76-item survey was designed and distributed to current women residents in radiation oncology in 2017-2018. Analyses describe personal, program, and family characteristics and experiences before and after joining the field. Results Of 170 female residents surveyed, 125 responded (74% response rate). Over one-quarter were in programs with ≤2 female residents (29%) and ≤2 female attendings (29%). One-third (34%) reported having children. Over half (51%) reported that lack of mentorship affected career ambitions. Over half (52%) agreed that gender-specific bias existed in their programs, and over a quarter (27%) reported they had experienced unwanted sexual comments, attention, or advances by a superior or colleague. Only 5% reported no symptoms of burnout. Almost all (95%) agreed that radiation oncology is perceived as family friendly; however, only 52% agreed that it actually is. An overwhelming majority (90%) expressed interest in joining a professional group for women in radiation oncology. Conclusions In the first study to our knowledge to focus specifically on the experiences of women residents in radiation oncology, a number of areas for potential improvement were highlighted, including isolation and underrepresentation, mentorship needs, bias and harassment, and gender-based obstacles such as need for support during pregnancy and motherhood. These findings support the organization of groups such as the Society for Women in Radiation Oncology, which seeks to target these needs to promote gender equity.

When pancreatic cancer cannot be removed surgically, patients frequently experience morbidity and death from progression of their primary tumor. Radiation therapy (RT) cannot yet substitute for an operation because radiation causes fatal bleeding and ulceration of the nearby stomach and intestines before achieving tumor control. There are no FDA-approved medications that prevent or reduce radiation-induced gastrointestinal injury. Here, we overcome this fundamental problem of anatomy and biology with the use of the oral EGLN inhibitor FG-4592, which selectively protects the intestinal tract from radiation toxicity without protecting tumors. A total of 70 KPC mice with autochthonous pancreatic tumors received oral FG-4592 or vehicle control ± ablative RT to a cumulative 75 Gy administered in 15 daily fractions to a limited tumor field. Although ablative RT reduced complications from local tumor progression, fatal gastrointestinal bleeding was observed in 56% of mice that received high-dose RT with vehicle control. However, radiation-induced bleeding was completely ameliorated in mice that received high-dose RT with FG-4592 (0% bleeding, P < 0.0001 compared with vehicle). Furthermore, FG-4592 reduced epithelial apoptosis by half (P = 0.002) and increased intestinal microvessel density by 80% compared with vehicle controls. EGLN inhibition did not stimulate cancer growth, as treatment with FG-4592 alone, or overexpression of HIF2 within KPC tumors independently improved survival. Thus, we provide a proof of concept for the selective protection of the intestinal tract by the EGLN inhibition to enable ablative doses of cytotoxic therapy in unresectable pancreatic cancer by reducing untoward morbidity and death from radiation-induced gastrointestinal bleeding. Significance: Selective protection of the intestinal tract by EGLN inhibition enables potentially definitive doses of radiation therapy. This might allow radiation to be a surgical surrogate for unresectable pancreatic cancer.

IMPORTANCEPatients with localized squamous cell carcinoma of the anus (SCCA) who experience treatment toxicity or recurrences have few therapeutic options.Investigation into the microbiome’s influence on treatment toxicity or its potential use as a predictive biomarker in this rare disease could improve these patients’ outcomes.OBJECTIVETo longitudinally characterize the SCCA tumor microbiome and assess its association with treatment-related toxicities.DESIGNProspective cohort study.SETTINGSingle tertiary cancer center.PARTICIPANTSTwenty-two patients with biopsy-confirmed non-metastatic SCCA receiving standard-of-care chemoradiotherapy as part of an Institutional Review Board-approved study from April 2017 to July 2019.MAIN OUTCOMES AND MEASURESDiversity and taxonomic characterization of the SCCA microbiome throughout chemoradiotherapy using swab-based anorectal microbial specimen collection and 16S rRNA gene sequencing.RESULTSTwenty-two SCCA patients were included in this study with a median (range) age of 58.5 (39-77), and 18 (82%) were women. Alpha diversity remained relatively stable throughout chemoradiotherapy, except for decreases in the Chao1 (P=0.03) and Observed Features (P=0.03) indices at week 5 relative to baseline. Tumor microbial compositions measured using weighted UniFrac changed significantly by the end of treatment (P=0.03). Linear discriminant analysis effect sizes revealed differential enrichment of bacteria at specific time points, including the enrichment of Clostridia at both baseline and follow-up and the enrichment of Corynebacterium at week 5. Patients experiencing high toxicity at week 5 had higher relative abundances of Clostridia, Actinobacteria, and Clostridiales at baseline (P=0.03 for all).CONCLUSIONS AND RELEVANCEOur study presents the first longitudinal characterization of the SCCA microbiome throughout chemoradiation. The tumor microbiome undergoes significant changes during and after chemoradiotherapy, and patient-reported toxicity levels are associated with patients’ microbial profiles. Further studies into these microbial characterizations and associations are needed to elucidate the tumor microbiome’s role in predicting treatment-related outcomes for SCCA patients.Key PointsQUESTIONHow does the squamous cell anal tumor microbiome change during chemoradiotherapy, and how do these changes influence treatment-related toxicity?FINDINGSProspective longitudinal characterization of anal cancer patients revealed significant modulation of the local tumor microbiome in response to chemoradiotherapy including shifts in overall composition and differential enrichment of key taxa.Additionally, enrichment of specific taxa at baseline was associated with increased levels of treatment-related toxicities by the end of treatment.MEANINGThe anal tumor microbiome is significantly altered by chemoradiotherapy and could potentially serve as a biomarker for treatment-related toxicities.

PURPOSE/OBJECTIVE(S) Pelvic insufficiency fractures and decreased bone mineral density (BMD) can occur in women treated with radiotherapy (RT) for gynecologic cancers. The purpose of this study was to compare the magnitude of BMD changes inside and outside of the radiation field in patients treated with radiation +/- chemotherapy for cervical cancer. MATERIALS/METHODS In an IRB-approved prospective study, women (N = 78) with cervical cancer were assessed with serial tomographic scans and dual-energy x-ray absorptiometry (DXA) scans to evaluate the incidence of pelvic fractures (previously reported) and post-treatment BMD changes. Patients were treated with definitive RT or chemoradiation (CRT) at a single institution between 09/2008 and 07/2015. DXA scans were obtained at baseline (before CRT), 3 months, 1 year, and 2 years after completion of therapy. Serial BMD values at L1, L2, L3 and L4 were extracted from DXA reports. Patients with a pre-treatment history of pelvic fractures, bone metastases, or pelvic RT were excluded. The current analysis focused on a subset of 78 patients whose RT fields had upper borders below L1 and above L4, permitting a comparison of BMD changes in the field (L4) with those in a vertebral body outside the field (L1). Linear mixed models (LMM) were performed to examine the impact of radiotherapy on BMD change over time, and were adjusted for covariates (age, menopausal status, BMI, number of chemotherapy cycles). RESULTS The median age of 78 patients was 45.5 years (range 23-88); all received RT and 76/78 (97.5%) received concurrent CRT. Treatment was associated with a significant decline in BMD in all 4 lumbar vertebral bodies over time, P < 0.05 with nadir at 3 months (L4) and 1 year (L1). By pairwise comparisons at 3 months and 2 years after treatment, BMD in L4 (inside RT field, P = 0.037) significantly improved while BMD in L1 (outside RT field) did not significantly change. After controlling for covariates noted above, there was no significant difference in BMD between 3 months and 2 years. Levels of C-terminal telopeptide of type I collagen (P = 0.018), bone alkaline phosphatase (P < 0.001), and number of chemotherapy cycles (P = 0.031) were significant predictors of L1 BMD loss. A trend of higher BMD at all time points was found for patients who were premenopausal versus postmenopausal at study entry. At 1- and 2-years of follow-up, trends towards BMD at levels higher than baseline were seen for patients who received hormone replacement therapy (HRT) after RT. CONCLUSION Significant BMD loss following radiation treatment in all lumbar vertebrae (both in and out of field) was observed. On multivariate analysis, in-field vertebral bodies experienced no additional significant BMD decline earlier than those out-of-field, suggesting multifactorial contributors to bone density loss. HRT may improve BMD recovery and emphasizes the need for HRT after radiotherapy in appropriate premenopausal women. AUTHOR DISCLOSURE J. Wu: None. D.S. Lakomy: None. B. Fellman: None. M.P. Salcedo: IGCS-International Gynecologic Cancer Society, Brazilian Federation of Gynecology and Obstetricians (FEBRASGO)/BRAZIL (Federacao Brasileira de Ginecologia e Obstetricia, FEBRASGO). A. Sood: Consultant; Kiyatec, Astra Zeneca. Stock; BioPath. sponsored research; M-Trap. A. Jhingran: American Board of Radiology. A.H. Klopp: Research Grant; MD Anderson Cancer Center SPORE Grant. R.B. Iyer: None. C. Jimenez: None. L. Colbert: None. K. Schmeler: None. P.J. Eifel: Travel Expenses; National Cancer Center Network. Stock; Apple Computer. L.L. Lin: Employee; VA Hospital. Research Grant; AstraZeneca. Travel Expenses; AstraZeneca.

Human papillomavirus (HPV) infection causes 600,000 new cancers worldwide each year. HPV-related cancers express the oncogenic proteins E6 and E7, which could serve as tumor-specific antigens. It is not known whether immunity to E6 and E7 evolves during chemoradiotherapy (CRT) or affects survival. We used functional T-cell assays to identify candidate HPV-specific T-cells and T- cell motifs common across 86 patients with HPV-related cancers. These HPV-specific clones and E7-related motifs expanded over the course of treatment, whereas non-HPV-specific T-cells did not. In HPV16+ patients, improved recurrence-free survival was associated with this HPV-responsive T-cell expansion during CRT.

The concept of mentorship has existed for a long time and has proved to be especially beneficial in medicine. Identifying and working with a mentor or mentor team can be a multifaceted approach and can occur through both formal and informal channels as well as both inside and outside one’s field. There are several approaches to mentorship with one holistic model in the context of medical practice encompassing educational, professional, and personal aspects. Special considerations such as diversity in background and gender are important in elevating the status of all trainees, while pitfalls and challenges to mentorship should be made aware as can occur in any relationship. As the field of radiation oncology is small and evidence-based, mentorship helps maintain positive associations in the field, and more effort is needed to formalize sponsorship programs to help advance the careers of trainees and early-career faculty. Here, we offer practical ways to maximize the mentorship experience.

Background A diverse and abundant gut microbiome can improve cancer patients’ treatment response; however, the effect of pelvic chemoradiotherapy (CRT) on gut diversity and composition is unclear. The purpose of this prospective study was to identify changes in the diversity and composition of the gut microbiome during and after pelvic CRT. Materials and methods Rectal swabs from 58 women with cervical, vaginal, or vulvar cancer from two institutions were prospectively analyzed before CRT (baseline), during CRT (weeks 1, 3, and 5), and at first follow-up (week 12) using 16Sv4 rRNA gene sequencing of the V4 hypervariable region of the bacterial 16S rRNA marker gene. 42 of these patients received antibiotics during the study period. Observed operational taxonomic units (OTUs; representative of richness) and Shannon, Simpson, Inverse Simpson, and Fisher diversity indices were used to characterize alpha (within-sample) diversity. Changes over time were assessed using a paired t-test, repeated measures ANOVA, and linear mixed modeling. Compositional changes in specific bacteria over time were evaluated using linear discriminant analysis effect size. Results Gut microbiome richness and diversity levels continually decreased throughout CRT (mean Shannon diversity index, 2.52 vs. 2.91; all P Conclusion After CRT, the diversity of the gut microbiomes in this population tended to return to baseline levels by the 12 week follow-up period, but structure and composition remained significantly altered. These changes should be considered when designing studies to analyze the gut microbiome in patients who receive pelvic CRT for gynecologic cancers.

The microbiome, which refers to the microbiota within a host and their collective genomes, has recently been demonstrated to play a critical role in cancer progression, metastasis, and therapeutic response. The microbiome is known to affect host immunity, but its influence on human papilloma virus (HPV) gynecologic malignancies remains limited and poorly understood. To date, studies have largely focused on the cervicovaginal microbiome; however, there is growing evidence that the gut microbiome may interact and substantially affect therapeutic response in gynecologic cancers. Importantly, new developments in microbiome sequencing and advanced bioinformatics technologies have enabled rapid advances in our understanding of the gut and local tumor microbiota. In this review, we examine the evidence supporting the role of the microbiome in HPV-associated cervical intraepithelial neoplasia (CIN) and cervical cancer, explore characteristics that influence and shape the host microbiota that impact HPV-driven carcinogenesis, and highlight potential approaches and considerations for future and ongoing research of the microbiome's effect on HPV-associated cancer.

The purpose of this study was to quantitatively evaluate the visibility and artifacts of commercially available fiducial markers in order to optimize their selection for image-guided stereotactic body radiation therapy (SBRT). From six different vendors, we selected 11 fiducials commonly used in image-guided radiation therapy (IGRT); the fiducials varied in material composition (gold, platinum, carbon), shape (cylindrical, notched/linear, coiled, ball-like, step), and size measured in terms of diameter (0.28-1.0 mm) and length (3.0-20.0 mm). Each fiducial was centered in 4-mm bolus within a 13-cm-thick water-equivalent phantom. Fiducials were imaged with use of a simulation computed tomography (CT) scanner, a CT-on-rails system, and an onboard cone-beam CT system. Acquisition parameters were set according to clinical protocols. Visibility was assessed in terms of contrast and the Michelson visibility metric. Artifacts were quantified in terms of relative standard deviation and relative streak artifacts level (rSAL). Twelve radiation oncologists ranked each fiducial in terms of clinical usefulness. Contrast and artifacts increased with fiducial size. For CT imaging, maximum contrast (2722 HU) and artifacts (rSAL=2.69) occurred for the largest-diameter (0.75 mm) platinum fiducial. Minimum contrast (551 HU) and reduced artifacts (rSAL=0.65) were observed for the smallest-diameter (0.28 mm) gold fiducial. Carbon produced the least severe artifacts (rSAL = 0.29). The survey indicated that physicians preferred gold fiducials with a 0.35- to 0.43-mm diameter, 5- to 10-mm length, and a coiled or cylindrical shape that balanced contrast and artifacts. We evaluated 11 different fiducials in terms of visibility and artifacts. The results of this study may assist radiation oncologists who seek to maximize contrast, minimize artifacts, and/or balance contrast versus artifacts by fiducial selection., 22 pages