American Society For Radiation Oncology Research Articles

Abstract 4846: Geographic and physician-level variation in the use of hypofractionated radiotherapy for breast cancer in the U.S.: A cross-classified multilevel analysis

Abstract Hypofractionated whole-breast irradiation (HF-WBI), a radiotherapy with a larger dose per fraction and a shorter schedule for early-stage breast cancer patients post breast-conserving surgery, shows equivalent safety and efficacy compared to conventionally fractionated whole-breast irradiation (CF-WBI) regarding local recurrence and disease-free survival. While several countries have set HF-WBI as the preferred standard of care for these patients, its uptake in the U.S. has lagged behind expectations. We used the Health Care Cost Institute (HCCI) database 2008-2017, covering a third of the U.S. employer-sponsored insurance population, to identify early-stage breast cancer patients. Patients were clustered at different geographic levels (Census region, state, core-based statistical area (CBSA), hospital referral region of Dartmouth Atlas, and zip code) and the radiation oncologist level. These two levels are cross-nested. We used a Bayesian cross-classified multilevel logistic model to simultaneously model the geographic units variability and physician-level variability in HF-WBI use across the U.S. Variation metrics included intracluster correlation coefficient (ICC) and median odds ratios (MOR). ICC with a value of 0 is equivalent to MOR of 1, indicating identical outcomes across all levels. After accounting for these variations in the cross-classified multilevel model framework, we evaluated the association between HF-WBI use and clinical and demographic factors.Our study included 79,747 women (74.0%) who underwent CF-WBI and 27,999 (26.0%) who received HF-WBI. HF-WBI adoption increased over time (2008-2017). Variability across radiation oncologists (ICC = 0.272, MOR = 2.88) was notably larger than geographic areas variability. Variability across CBSA (ICC = 0.097, MOR = 1.76) was the strongest among all the geographic levels. The variation in HF-WBI use was mainly attributed to physician-level variability (ICC=0.222, MOR=2.59) based on the cross-classified multilevel model. No substantial differences were found between young (aged 64 or younger with commercial health plans) and older patients (aged 65 or older with Medicare Advantage plans) in terms of both geographic and physician-level variations. After accounting for variability in radiation oncologists and CBSAs, older age, non-reception of chemotherapy, and several community-level factors, including longer distance from home to facility and higher community education level, were associated with a higher likelihood of HF-WBI use. These results may lend insights into potential facilitators/barriers to HF-WBI uptake. Future studies can further investigate the impact of the 2018 American Society for Radiation Oncology (ASTRO) guideline and the Covid-19 pandemic on HF-WBI use, which would illuminate potential improvements of healthcare practices. Citation Format: Yijia Sun, Loren Saulsberry, Chuanhong Liao, Donald Hedeker, Dezheng Huo. Geographic and physician-level variation in the use of hypofractionated radiotherapy for breast cancer in the U.S.: A cross-classified multilevel analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4846.

National Survey of Oncologists' Knowledge, Attitudes, and Practice Behaviors: Caring for Cancer Patients Experiencing Incarceration.

Cancer is the leading cause of illness-related death in state prisons in the United States. The experiences of physicians providing oncological care to individuals experiencing incarceration are underexplored. The study aims were to evaluate knowledge, attitudes, and practices of oncologists caring for cancer patients who are incarcerated. An online survey was distributed to a random sample of 150 oncologists from the American Society of Clinical Oncology and the American Society for Radiation Oncology from July 2020 to December 2021. Statistical analyses included two proportion Z-test, Fisher's exact test, Kruskal-Wallis test, and Cramer's V to estimate factors associated with attitudes and barriers to care. Of the 55 respondents (36.7% response rate), 21 were medical oncologists and 34 were radiation oncologists. Academic center oncologists were more likely to report caring for incarcerated patients than community or private practice oncologists (p = .04). Most (53%) incorrectly reported "heart disease" as the leading cause of death, as opposed to "cancer" (15% identified correctly). Oncologists practicing at both academic and community centers were more likely to report care coordination barriers than oncologists at academic or community centers (p < .01). We identified potential barriers in caring for incarcerated cancer patients. Future studies should explore ways to improve care coordination between oncology teams and prisons.

Comparative Analysis of US Guidelines for the Management of Cutaneous Squamous Cell and Basal Cell Carcinoma.

This study presents a comparative analysis of recently published guidelines to manage cutaneous squamous cell carcinoma (cSCC) and cutaneous basal cell carcinoma (cBCC) within the United States (US). A PubMed database search was performed for the time period between June 1, 2016, and December 1, 2022. A comprehensive comparison was performed in the following clinical interest areas: staging and risk stratification, management of primary tumor and regional nodes with curative intent, and palliative treatment. Guidelines from 3 organizations were analyzed: the American Academy of Dermatology (AAD), the National Comprehensive Cancer Network (NCCN), and the American Society for Radiation Oncology (ASTRO). The guidelines used different methodologies to grade evidence, making comparison difficult. There was agreement that surgery is the preferred treatment for curative cBCC and cSCC. For patients ineligible for surgery, there was a consensus to recommend definitive radiation. AAD and NCCN recommended consideration of other topical modalities in selected low-risk cBCC. Postoperative radiation therapy (PORT) was uniformly recommended in patients with positive margins that could not be cleared with surgery and in patients with nerve invasion. The definition and extent of nerve invasion varied. All guidelines recommended surgery as the primary treatment in patients with lymph node metastases in a curative setting. The criteria used for PORT varied; NCCN and ASTRO used lymph node size, number of nodes, and extracapsular extension for recommending PORT. Both NCCN and ASTRO recommend consideration of systemic treatment along with PORT in patients with extracapsular extension. Conclusion: US guidelines provide contemporary and complementary information on the management of cBCC and cSCC. There are opportunities for research, particularly in the areas of staging, indications for adjuvant treatment in curative settings, extent of nerve invasion and prognosis, and the role of systemic treatments in curative and palliative settings.

Pilot Study Assessing Student Interest in Combined Residency Training Pathways With Radiation Oncology

Most medical students have limited exposure to radiation oncology (RO) before deciding which specialty to choose for residency. This may limit the number and diversity of RO applicants. The purpose of this study was to determine students' views on a combined pathway program of RO with internal medicine (IM), as well as other related medical specialties, as a potential means of overcoming barriers to interest in RO and the early decision point to solo training in a highly specialized field. In July to August 2022, all 299 United States student and postgraduate year 1 members of the American Society for Radiation Oncology were sent an electronic survey assessing their views on advantages and disadvantages of a combined IM/RO training pathway, and interest in several options of combined pathway programs. Eighty participants completed the survey (response rate 27%). Thirty-four (43%) were very or extremely interested in IM/RO residency (median Likert-type rating 3, IQR 2-4). The most important potential advantages of an IM/RO pathway included greater flexibility in employment options (n = 51, 64%), enhanced general medical knowledge to facilitate ambitions in other career pathways (n = 46, 58%), improved patient care (n = 43, 54%), and having a pathway for combined hematologic/oncology and RO board certification (n = 46, 58%). In comparison to IM/RO, participants were significantly more interested in a combined RO and hematology/oncology program (median Likert-type rating 5, IQR 5-5, P = .005). Among the subgroup of 26 survey participants who believed it less likely they would apply for RO residency, 18 (69%) thought an IM/RO pathway would increase their interest in RO (median Likert-type rating 4, IQR 3-5). Interest in IM/RO did not differ by gender, race, or ethnicity. Combined training pathways involving RO were viewed positively by survey respondents, and may be particularly appealing to those less committed to a career in RO. Further research will help guide recommendations for the creation of these programs.

Impact of SSO-ASTRO Margin Guidelines on Re-excision Rate in Breast-conserving Surgery: A Single-center Experience.

Breast-conserving surgery (BCS) has been historically linked with a high rate of re-excision. To address this issue, the Society of Surgical Oncology (SSO) and the American Society for Radiation Oncology (ASTRO) developed consensus guidelines in 2014 to standardize practices and improve clinical outcomes for BCS patients. In our tertiary cancer care hospital, we assessed the impact of these guidelines on the re-excision rate following BCS. We conducted a retrospective study on breast cancer patients who underwent BCS at the Shaukat Khanum Memorial Cancer Hospital and Research Centre in Lahore, Pakistan. The study compared the re-excision rate before the implementation of the SSO-ASTRO consensus guidelines (November 2015-July 2017) and after the implementation (January 2018-August 2019). Margins were considered positive if "ink on tumor" was present and negative if "no ink on tumor" was present. Fisher's exact test or Chi-square test was used to compare the re-excision rates between the pre- and post-guideline periods. A total of 919 patients were identified, with 533 from the pre-guideline period and 386 from the post-guideline period. Of the 919 patients, 31 with ductal carcinoma in situ (DCIS) were excluded from the re-excision analysis because the guidelines were not implemented on the DCIS. Furthermore, the overall rate of re-excision in our data was 4.3%. The re-excision rate decreased from 71.1% to 28.9% (P ≤ 0.05) following the adoption of the guidelines. We observed a statistically significant decrease in the re-excision rate after implementing the SSO-ASTRO guidelines. Implementation of the SSO-ASTRO margin guidelines led to a notable decrease in the overall re-excision rate in our data set. These findings suggest that continued adherence to the guidelines may lead to a further reduction in the re-excision rate in the future.

Practical Implications of the American Society for Radiation Oncology Radiation Oncology Case Rate Program Proposal for Radiation Oncologists

The American Society for Radiation Oncology has proposed the Radiation Oncology Case Rate Program (ROCR) to advocate for fair reimbursement for radiation oncologists. ROCR would replace Medicare fee-for-service with a case rate payment for each of the 15 most common cancer types treated with external beam or stereotactic radiation therapy. This topic discussion attempts to provide a concise overview of the practical implications for radiation oncologists should the ROCR payment program be legislated by Congress and subsequently implemented by the Center for Medicare and Medicaid Services. This topic discussion covers the practical changes to billing and reimbursement, the Health Equity Achievement in Radiation Therapy payment, the Quality of Care requirement, and the available tool to calculate the effect of the ROCR based on an individual practice's case mix.

Assessment of Eligibility and Utilization of Accelerated Partial Breast Irradiation in Korean Breast Cancer Patients (KROG 22-15).

We investigated the proportions of patients eligible for accelerated partial breast irradiation (APBI) among those with pT1-2N0 breast cancer, based on the criteria set by the American Society for Radiation Oncology (ASTRO), the Groupe Européen de Curiethérapie and the European Society for Radiotherapy and Oncology (GEC-ESTRO), the American Brachytherapy Society (ABS), and the American Society of Breast Surgeons (ASBS). Additionally, we analyzed the rate of APBI utilization among eligible patients. Patients diagnosed with pT1-2N0 breast cancer in 2019 were accrued in four tertiary medical centers in Korea. All patients had undergone breast conserving surgery followed by radiotherapy, either whole breast irradiation or APBI. To determine which guideline best predicts the use of APBI in Korea, the F1 score and Matthews Correlation Coefficient (MCC) were determined for each guideline. A total of 1,251 patients were analyzed, of whom 196 (15.7%) underwent APBI. The percentages of eligible patients identified by the ASTRO, GEC-ESTRO, ABS, and ASBS criteria were 13.7%, 21.0%, 50.5%, and 63.5%, respectively. APBI was used to treat 54.4%, 37.2%, 27.1%, and 23.7% of patients eligible by the ASTRO, GEC-ESTRO, ABS, and ASBS criteria, respectively. The ASTRO guideline exhibited the highest F1 score (0.76) and MCC (0.67), thus showing the best prediction of APBI utilization in Korea. The proportion of Korean breast cancer patients who are candidates for APBI is substantial. The actual rate of APBI utilization among eligible patients may suggest there is a room for risk-stratified optimization in offering radiation therapy.

CodeX quality measures for cancer: Leveraging FHIR and mCODE to support digital quality measures.

466 Background: CodeX is a member-driven Health Level Seven (HL7) Fast Healthcare Interoperability Resources (FHIR) Accelerator, building a community to fast-track interoperable data modeling and implementation of new FHIR data standards leading to step-change improvements in patient care and research. The Quality Measures for Cancer project asks the question, “Can oncology quality measures be effectively authored and executed using minimal Common Oncology Data Elements (mCODE) — an initiative intended to assemble a core set of structured data elements for oncology electronic health records (EHRs) — and FHIR, given that current measures must be manually collected and abstracted?” The Quality Measures for Cancer project aims to provide a less burdensome path for all parties involved in the quality measure lifecycle to share standardized oncology quality measure data. Methods: The Quality Measures for Cancer project has assembled a team of leading healthcare professionals from American Society of Clinical Oncology (ASCO), American Society for Radiation Oncology (ASTRO), Telligen, Evernorth, and MITRE to create a solution that demonstrates the ability to author and evaluate digital quality measures using FHIR standards, along with mCODE profiles and extensions, for value-based programs and clinical quality improvement in the oncology domain. More specifically, the initial project scope focuses efforts to: Develop a process for identifying the required discrete data to be used for data collection and aggregation; and prove that measures can be authored, generate accurate results, and can be executed using mCODE and FHIR. Results: Over the first year of project work, the Quality Measures for Cancer team has demonstrated that mCODE and FHIR can be used to author and execute oncology measures. The team has fully authored and tested two proof of concept ASCO antiemetic electronic clinical quality measures (eCQMs) using mCODE, FHIR, and the Quality Measures Implementation Guide. A demonstration is available to show the team's recent success with testing the feasibility and value of authoring and executing the two ASCO antiemetic eCQMs using mCODE and FHIR, evaluating the measure, and discussing how burden is reduced for providers, as well as submitters and receivers of quality measures. Conclusions: Long-term, the CodeX Quality Measures for Cancer team posits that by leveraging mCODE and FHIR to assist in the development and authoring of innovative oncology quality measures, real and impactful insight and assessment into true quality measures could be made if mCODE and other FHIR Implementation Guides are implemented and leveraged by an ecosystem of health organizations. This project is acting as an exemplar showing what can be achieved by leveraging several quality-specific FHIR Implementation Guides to create and roll out new, innovative quality measures.

In Pursuit of Meaningfulness in the Biomedical Literature – Notes from a Scrap Booklet

"guestProfessor Søren M. Bentzen is the Director of the Division of Biostatistics and Bioinformatics, Department of Epidemiology and Public Health, University of Maryland School of Medicine, USA, and he is also an Adjunct Professor of Radiobiology and Medical Physics, University of Copenhagen, Denmark. Dr. Bentzen received a Master of Sciences in physics and mathematics, a PhD in medical image analysis, and he is a doctor of medical science in quantitative clinical radiobiology. He was one of the leaders of the Quantitative Analyses of Normal Tissue Effects in the Clinic (QUANTEC) initiative, and serves as a member of the Pediatric Normal Tissue Effects in the Clinic (PENTEC) steering committee. He was also a member of the American Society for Radiation Oncology (ASTRO) Task Forces to develop evidence-based guidelines on the appropriate fractionation for whole breast irradiation and for localized prostate cancer. He has served as chair or member of 17 (seven currently active) Independent Data and Safety Monitoring Committees or Trial Steering Committees and as co-chair for Translational Research for two Radiation Therapy Oncology Group (RTOG) phase III trials. He has published more than 500 original papers and book chapters, has presented &gt;370 invited lectures, and he currently serves on 10 international cancer journal editorial boards. His main research interests include bioeffect modeling; biomathematics; applied biostatistics; clinical trial design; evidence-based medicine; late effects of radiotherapy; clinical radiobiology; integration of data from genomics, proteomics, and molecular imaging into novel therapeutic"

Quality and Safety Considerations in Image Guided Radiation Therapy: An ASTRO Safety White Paper Update

This updated report on image guided radiation therapy (IGRT) is based on a consensus-based white paper previously published by the American Society for Radiation Oncology (ASTRO) addressing patient safety. In the past decade, IGRT technology and procedures have progressed significantly and are now more commonly used. The use of IGRT has now extended beyond high-precision treatments, such as stereotactic radiosurgery and stereotactic body radiation therapy, and into routine clinical practice for many treatment techniques and anatomic sites. Therefore, quality and treatment planning and delivery considerations for these techniques are paramount for patient safety. In 2021, ASTRO convened an interdisciplinary task force to assess the original IGRT white paper and update content where appropriate. Recommendations were created using a consensus-building methodology, and task force members indicated their level of agreement based on a 5-point Likert scale from "strongly agree" to "strongly disagree." A prespecified threshold of ≥75% of raters who selected "strongly agree" or "agree" indicated consensus. The IGRT white paper was published (Pract Radiat Oncol. 2022 Dec) and endorsed by the American Association of Physicists in Medicine (AAPM), American Association of Medical Dosimetrists, and American Society of Radiologic Technologists. Since the first IGRT paper was published by ASTRO in 2013, significant technological advancement has taken place. New and updated considerations in personnel requirements, staffing, education and training, equipment and technological requirements, quality management and assurance, IGRT program management, and safety considerations were reported. A 17-point consensus was reached and recommended in 5 areas surrounding program development, quality assurance, quality management, treatment delivery, and vendor engagement (Table 5, Summary of key recommendations). This IGRT white paper builds on the previous version and uses other guidance documents to primarily focus on processes related to quality and safety. IGRT requires an interdisciplinary team-based approach, staffed by appropriately trained specialists, as well as significant personnel resources, specialized technology, and implementation time. A thorough feasibility analysis of resources is required and should be discussed with all personnel before undertaking new imaging techniques. A comprehensive quality-assurance program must be developed to ensure IGRT is performed safely and effectively. As IGRT technologies continue to improve or emerge, existing practice guidelines should be updated regularly according to the latest AAPM Task Group reports. Patient safety in the application of IGRT is everyone's responsibility, and professional organizations, regulators, vendors, and end-users must demonstrate strong commitments to ensure that the highest levels of safety are achieved.

Gender and the Receipt of the Association of Residents in Radiation Oncology (ARRO) Educator of the Year Award

Despite an increase in female physicians in recent years, a gender disparity remains in the field of radiation oncology. We hypothesized that there may be a gender disparity in the receipt of ARRO educator awards. Using a database provided by the American Society for Radiation Oncology (ASTRO), annual award recipients were identified from 2010-2022. Data on Academic Institution, Year of Award, and Repeat Awardee Status were obtained through the ASTRO database. Publicly available websites were accessed to obtain data regarding gender, years post residency graduation, percent female/male faculty, size of residency program, and program director designation. H- indices were obtained from Scopus and used as a marker of academic productivity. Basic summary statistics, stratified by gender, were calculated for award year, years since graduation, percent of male faculty, and program size. A one-sample Z-test for proportions was utilized to assess if the proportion of female ARRO award winners each year from 2010 to 2022 was significantly less than the population average, defined as the proportion of female radiation oncology faculty members in the nominating universities that year. Secondary analyses used univariable binary logistic regression to identify any global associations between gender, year since gradation, or program size. The lowest proportion of female awardees occurred in 2013 (8 [14.3%] females vs. 48 [85.7%] males) and the greatest proportion of female awardees occurred in 2022 (19 [30.6%] females vs. 43 [69.4%] males). As compared to the proportion of female faculty members in nominating programs for that respective year, there were significantly fewer female awardees in the years of 2010 (18% female awardees vs. 32% female faculty members, p = 0.02) and 2013 (14% female awardees vs. 31% female faculty members, p = 0.01). There was a statistically significant rise in female awardees over the study period (p<0.01). On logistic regression analysis, large program size (10+ residents) (odds ratio [OR]: 6.86, 95% confidence interval [CI]: 2.71-23.1, p<0.001) and medium program size (5-9 residents) (OR: 4.05, 95% CI: 1.60-13.7, p<0.001) were associated with a greater proportion of female awardees as compared to small program size (1-4 residents). There was no association between awardee gender and years since graduation. A gender disparity is present in the receipt of ARRO Educator Awards. At an institutional level, residency Chiefs, Program Directors, and Chairs should work to ensure that a diverse slate of faculty are considered annually for the ARRO Educator Award with self-assessment of awardees over time to ensure demographic representation and inclusion. Efforts should also be made to recognize biases in resident evaluations of faculty with continued education about inherent biases.

Pilot Study Assessing Student Interest in Combined Residency Training Pathways with Radiation Oncology

Radiation oncology (RO) is a small, highly specialized field, which most medical students have limited exposure to before having to decide what specialty to apply to for their graduate medical education (GME). This may ultimately limit the number and diversity of RO applicants. The purpose of this pilot study was to determine students' views on a combined pathway program between RO with internal medicine (IM), as well as other related medical specialties, as a potential means of overcoming some of these barriers to student interest in RO and the early decision point to solo training in RO. An electronic survey was sent to 299 United States student members of the American Society for Radiation Oncology (ASTRO) between July-August 2022. Multiple choice and Likert-type questions were used to assess students' views on the potential advantages and disadvantages of a combined IM/RO training pathway, and interest in this potential combined pathway as well as other combined pathway programs with RO and other related subspecialties. The Mann-Whitney U and Kruskal-Wallis tests were used to compare the responses of subgroups of students stratified according to their gender identity, race, or ethnicity. The Wilcoxon signed rank test was used to compare all participants' interest in different combined pathway programs compared to RO/IM. Eighty participants completed the survey (response rate 27%). Thirty-four participants (43%) were either very or extremely interested in pursuing a combined IM/RO residency (median Likert-type rating 3, IQR 2-4). The duration of a combined IM/RO training considered most preferable or ideal was five years (n = 57, 71%) or six years (n = 21, 26%). The most important potential advantages of a combined IM/RO pathway included greater flexibility in employment options (n = 51, 64%), enhanced general medical knowledge to facilitate ambitions in other career pathways (n = 46, 58%), improved patient care (n = 43, 54%), and having a pathway for combined hematologic/oncology and RO board certification (n = 46, 58%). In comparison to IM/RO, participants were significantly more interested in a combined RO and hematology/oncology program (median Likert-type rating 5, IQR 5-5, p = 0.005). Among the subgroup of 26 students who believed that it was less likely that they would be applying for RO residency, 18 (69%) believed that the availability of an IM/RO pathway would increase their interest in applying to RO (median Likert-type rating 4, IQR 3-5). Interest in IM/RO did not differ by gender, race, or ethnicity. Combined training pathways involving RO were viewed positively by most survey respondents, comprised of student members of ASTRO. Such programs may be particularly appealing to those students who are interested, but less committed to pursuing, a career in RO. Further research will help guide recommendations for the creation of these programs.

Open RT Structures: A Solution for TG-263 Accessibility

BackgroundConsistency of nomenclature within radiation oncology is increasingly important as big data efforts and data sharing become more feasible. Automation of radiation oncology workflows depends on standardized contour nomenclature which enables toxicity and outcomes research, while also reducing medical errors and facilitating quality improvement activities. Recommendations for standardized nomenclature have been published in the American Association of Physicists in Medicine (AAPM) report from Task Group 263. Transitioning to TG-263 requires creation and management of structure template libraries and retraining of staff, which can be a considerable burden on clinical resources. Our aim is to develop a program that allows users to create TG-263 compliant structure templates in English, Spanish, or French to facilitate data sharing. Methods53 pre-made structure templates were arranged by treated organ based on an American Society for Radiation Oncology (ASTRO) consensus paper. Templates were further customized with common target structures, relevant OARs (e.g., Spleen for anatomically relevant sites such as gastroesophageal junction or stomach), sub-site specific templates (e.g. partial breast, whole breast, intact prostate, postoperative prostate, etc.) and brachytherapy templates. An informal consensus on OAR and target coloration was also achieved, though color selections are fully customizable within the program. ResultsThe resulting program is usable on any Windows system and generates template files in practice-specific DICOM or XML formats, extracting standardized structure nomenclature from an online database maintained by members of the TG-263U1 Task Group which ensures continuous access to up-to-date templates. ConclusionsWe have developed a tool to easily create and name DICOM-RT structures sets that are TG-263-compliant for all planning systems utilizing the DICOM standard. The program and source code are publicly available via GitHub, encouraging feedback from community users for improvement and guide further development.

The Role of Radiation Therapy in Adult and Pediatric Keloid Management: A National Survey of Radiation Oncologists.

Radiation therapy is a promising modality for treating keloids after surgical excision. However, it is currently not standard practice among physicians because of concern surrounding the risk of radiation-induced secondary cancers, especially among pediatric patients. There is minimal research assessing the complications for radiation therapy in keloid management. The goal of this study was to determine radiation oncologists' perspectives about the utility and appropriateness of radiation therapy for keloid management in both adult and pediatric patients. This study also aimed to characterize radiation modality, dose, fractionation, and secondary complications observed by providers. An electronic survey was delivered to 3102 members of the American Society for Radiation Oncology. The survey subjects were radiation oncologists who are currently practicing in the United States. Rates of responses were analyzed. A total of 114 responses from practicing radiation oncologists were received. Of these, 113 providers (99.1%) supported radiation therapy for keloid management in adults, whereas only 54.9% supported radiation therapy for pediatric patients. Of 101 providers that treated adults in the past year, the majority used external beam: electrons (84.2%), applied 3 fraction regimens (54.4%), and delivered radiation within 24 hours postexcision (45.5%). In pediatric patients, only 42 providers reported treating at least 1 patient. The majority used electron beam radiation (76.2%), applied 3 faction regimens (65%), and delivered radiation on the same day of keloid excision (50.0%) The main concern when treating pediatric patients were risk of secondary malignancy (92.1%). Although radiation therapy appears to be a widely accepted adjuvant treatment option for adults with keloids, the use of radiation therapy for pediatric patients is less widely accepted because of concerns regarding secondary malignancy. The findings suggest additional studies need to be carried out to assess the risk of those complications.

Assessment of Medical Student Research Mentorship in Radiation Oncology

Mentored medical student (MS) research opportunities in radiation oncology (RO) provide in-depth exposure to the specialty and may promote greater interest in a career in RO. Many radiation oncologists conduct research; however, the extent to which they directly engage MSs in their research is unknown. The purpose of this study was to characterize MS authorship in American Society for Radiation Oncology (ASTRO) journals. The byline and abstract of all scientific articles (ie, clinical, basic science, training/education) and case reports published from 2019 to 2021 in the International Journal of Radiation Oncology, Biology, and Physics; Practical Radiation Oncology; and Advances in Radiation Oncology were reviewed. Characteristics of MSs and senior authors are reported. A total of 105 of 1785 articles (5.8%) included an MS author, among which 72 (68.6%) were clinical, 13 training/education (12.4%), 12 case reports (11.4%), and 8 basic science (7.6%). MS authors were more common for publications in Advances in Radiation Oncology (9.0%) than Practical Radiation Oncology (6.4%) or the International Journal of Radiation Oncology, Biology, and Physics (4.2%; P=.002). There were 125 unique MS authors from 72 institutions, among which 40 were first author (32.0%), 28 second author (22.4%), and 57 third (or higher) author (45.6%). There were 88 unique senior authors from 55 institutions, among which 10 (11.3%) were on 2 or more MS publications, and 57 (64.7%) shared the same institution as the MS. The median number of articles per mentor institution was 1 (interquartile range, 1-2), and the mentor institutions in the upper quartile in terms of number of MS publications accounted for 53 (50.5%) of all MS publications. Few publications in American Society for Radiation Oncology journals include MS authors with mentorship disproportionately from a small number of academic faculty at select institutions. These findings suggest that there is great potential for radiation oncologists to proactively engage more students in their work.

The Impact of Breast-Conserving Surgery Re-excision on Patient-Reported Outcomes Using the BREAST-Q.

Approximately 14% of women undergoing breast-conserving surgery (BCS) require re-excision to achieve negative margins following the Society of Surgical Oncology (SSO) and American Society for Radiation Oncology (ASTRO) margin guidelines, which may influence patient-reported outcomes (PROs). Few studies have assessed the impact of re-excision on PROs following BCS. Women with stage 0-III breast cancer undergoing BCS who completed a BREAST-Q PRO measure from 2010 to 2016 were identified from a prospective database. Baseline characteristics were compared between women who underwent one BCS and those who underwent ≥ 1 re-excision surgery for positive margins (R-BCS). Linear mixed models were used to analyze associations between number of excisions and BREAST-Q scores over time. Of 2543 eligible women, 1979 (78%) had one BCS and 564 (22%) had R-BCS. Younger age, lower BMI, surgery pre-SSO Invasive Guidelines issuance, ductal carcinoma in situ (DCIS), multifocal disease, radiation therapy receipt, and endocrine therapy omission were more common in the R-BCS group. Breast satisfaction and sexual well-being were lower in the R-BCS group 2years postoperatively. There were no differences in psychosocial well-being between groups over 5 years. On multivariable analysis, re-excision was associated with lower breast satisfaction and sexual well-being (p= 0.007 and p= 0.049, respectively), but there was no difference in psychosocial well-being (p= 0.250). Women with R-BCS had lower breast satisfaction and sexual well-being 2 years postoperatively, but this difference did not remain long term. Psychosocial well-being in women who underwent one BCS were largely comparable over time to the R-BCS group. These findings may help in counseling women who are concerned about satisfaction and quality-of-life outcomes with BCS if re-excision is necessary.

Accelerated partial breast irradiation (APBI) for ductal carcinoma in situ.

e12516 Background: Landmark studies of accelerated partial breast irradiation (APBI) included patients with DCIS, but with limited guidance regarding subgroups of in situ disease. Suitability criteria defined by national guidelines for APBI are narrowly constrained among those with DCIS, and controversy persists regarding optimal patient selection. Here, we report disease outcomes for a heterogeneous cohort of patients with DCIS who received APBI. Methods: Using a prospectively maintained institutional database, we identified patients with DCIS who underwent lumpectomy and adjuvant APBI from 2000 to 2022. Clinicopathologic characteristics were collected, and patients were classified as suitable, cautionary, or unsuitable for APBI by the latest American Society for Radiation Oncology (ASTRO) criteria. Outcomes of interest included local recurrence (LR), overall survival (OS), and follow up time. Cumulative incidence functions were calculated to estimate the incidence of LR over time. All statistical analyses were performed in R version 4.2.2. Results: The cohort comprised 176 patients, median age 60 years (IQR 52, 66). Median DCIS size was 9 mm (IQR 4, 15 mm), and approximately 20% had multifocal disease. Most patients had negative final surgical margins (160, 91%), with 10 patients having ≤2 mm margins and 6 having ≤1 mm margins for DCIS. 18 (10%) patients had nuclear grade I disease, 111 (63%) had grade II disease, and 33 (19%) had grade III disease, with a small subset classified as grade I-II or II-III. Most patients (161, 91%) had ER+ DCIS, and 72 (41%) received endocrine therapy. By ASTRO criteria, 118 (67%) patients were suitable for APBI, 57 (32%) cautionary, and 1 (0.6%) was unsuitable. At a median 24 months of follow up (range 2 to 127 months) we observed only one LR, yielding a 2-year LR rate of 0.6%. The LR occurred in the cautionary group, yielding a 2-year LR rate of 1.8% for the cautionary subset. The patient with LR was 56 years old, with 24 mm of high grade DCIS, ER+, with lumpectomy to negative margins, and did not receive endocrine therapy. No breast cancer mortality events were observed. Conclusions: Our early-term results exhibit excellent local control for patients with DCIS who received lumpectomy and APBI, even among those classified as “cautionary” by national guidelines. Although our findings are limited by short follow up, these results suggest that broadening the application of APBI for patients with DCIS may warrant further investigation.

Evaluation of the ESMO-Magnitude of Clinical Benefit Scale version 1.1 (ESMO-MCBS v1.1) for adjuvant radiotherapy in breast cancer

The European Society of Medical Oncology (ESMO) has suggested using the ESMO-Magnitude of Clinical Benefit Scale (MCBS) to grade the magnitude of clinical benefit of cancer therapies. This approach has not been applied to radiation therapy (RT) yet. We applied the ESMO-MCBS to experiences describing the use of RT to assess (1) the 'scoreability' of the data, (2) evaluate the reasonableness of the grades for clinical benefit and (3) identify potential shortcomings in the current version of the ESMO-MCBS in its applicability to RT. We applied the ESMO-MCBS v1.1 to a selection of studies in radiotherapy that had been identified as references in the development of American Society for Radiation Oncology (ASTRO) evidence-based guidelines on whole breast radiation. Of the 112 cited references, we identified a subset of 16 studies that are amenable to grading using the ESMO-MCBS. Of the 16 studies reviewed, 3/16 were scoreable with the ESMO tool. Six of 16 studies could not be scored because of shortcomings in the ESMO-MCBS v1.1: (1) in 'non-inferiority studies', there is no credit for improved patient convenience, reduced patient burden or improved cosmesis; (2) in 'superiority studies' evaluating local control as a primary endpoint, there is no credit for the clinical benefit such as reduced need for further interventions. In 7/16 studies, methodological deficiencies in the conduct and reporting were identified. This study represents a first step in determining the utility of the ESMO-MCBS in the evaluation of clinical benefit in radiotherapy. Important shortcomings were identified that would need to be addressed in developing a version of the ESMO-MCBS that can be robustly applied to radiotherapy treatments. Optimization of the ESMO-MCBS instrument will proceed to enable assessment of value in radiotherapy.

Comprehensive genomic profiling and treatment patterns across ancestries in advanced prostate cancer: a large-scale retrospective analysis

Men of African ancestry experience the greatest burden of prostate cancer globally, but they are under-represented in genomic and precision medicine studies. Therefore, we sought to characterise the genomic landscape, comprehensive genomic profiling (CGP) utilisation patterns, and treatment patterns across ancestries in a large, diverse, advanced prostate cancer cohort, to determine the impact of genomics on ancestral disparities. In this large-scale retrospective analysis, the CGP-based genomic landscape was evaluated in biopsy sections from 11 741 patients with prostate cancer, with ancestry inferred using a single nucleotide polymorphism-based approach. Admixture-derived ancestry fractions for each patient were also interrogated. Independently, clinical and treatment information was retrospectively reviewed for 1234 patients in a de-identified US-based clinicogenomic database. Prevalence of gene alterations, including actionable gene alterations, was assessed across ancestries (n=11 741). Furthermore, real-world treatment patterns and overall survival was assessed in the subset of patients with linked clincogenomic information (n=1234). The CGP cohort included 1422 (12%) men of African ancestry and 9244 (79%) men of European ancestry; the clinicogenomic database cohort included 130 (11%) men of African ancestry and 1017 (82%) men of European ancestry. Men of African ancestry received more lines of therapy before CGP than men of European ancestry (median of two lines [IQR 0-8] vs one line [0-10], p=0·029). In genomic analyses, ancestry-specific mutational landscapes were observed, but the prevalence of alterations in AR, the DNA damage response pathway, and other actionable genes were similar across ancestries. Similar genomic landscapes were observed in analyses that accounted for admixture-derived ancestry fractions. After undergoing CGP, men of African ancestry were less likely to receive a clinical study drug compared with men of European ancestry (12 [10%] of 118 vs 246 [26%] of 938, p=0·0005). Similar rates of gene alterations with therapy implications suggest that differences in actionable genes (including AR and DNA damage response pathway genes) might not be a main driver of disparities across ancestries in advanced prostate cancer. Later CGP utilisation and a lower rate of clinical trial enrolment observed in men of African ancestry could affect genomics, outcomes, and disparities. American Society for Radiation Oncology, Department of Defense, Flatiron Health, Foundation Medicine, Prostate Cancer Foundation, and Sylvester Comprehensive Cancer Center.

ASTRO Radiation Therapy Summary of the ASCO Guideline on Management of Stage III Non-Small Cell Lung Cancer

To develop a radiation therapy summary of recommendations on the management of locally advanced non-small cell lung cancer (NSCLC) based on the Management of Stage III Non-Small Cell Lung Cancer: American Society of Clinical Oncology Guideline, which was endorsed by the American Society for Radiation Oncology (ASTRO). The American Society of Clinical Oncology, ASTRO, and the American College of Chest Physicians convened a multidisciplinary panel to develop a guideline based on a systematic review of the literature and a formal consensus process, that has been separately published. A new panel consisting of radiation oncologists from the original guideline as well as additional ASTRO members was formed to provide further guidance to the radiation oncology community. A total of 127 articles met the eligibility criteria to answer 5 clinical questions. This summary focuses on the 3 radiation therapy questions (neoadjuvant, adjuvant, and unresectable settings). Radiation-specific recommendations are summarized with additional relevant commentary on specific questions regarding the management of preoperative radiation, postoperative radiation, and combined chemoradiation. Patients with stage III NSCLC who are planned for surgical resection, should receive either neoadjuvant chemotherapy or chemoradiation. The addition of neoadjuvant treatment is particularly important in patients planned for surgery in the N2 or superior sulcus settings. Postoperatively, patients who did not receive neoadjuvant chemotherapy should be offered adjuvant chemotherapy. The use of postoperative radiation for completely resected N2 disease is not routinely recommended. Unresectable patients with stage III NSCLC should ideally be managed with combined concurrent chemoradiation using a platinum-based doublet with a standard radiation dose of 60 Gy followed by consolidation durvalumab in patients without progression after initial therapy. Patients who cannot tolerate a concurrent chemoradiation approach can be managed either by sequential chemotherapy followed by radiation or by dose-escalated or hypofractionated radiation alone.