Background: The ASCO and American Society of Radiation Oncologists (ASTRO) have recently committed to initiatives on increasing URM representation in the radiation oncology workforce. This study aims to assess representation trends in radiation oncology training programs across five academic years in order to understand representation trends and better guide initiatives moving forward. Methods: Data on racial and ethnic representation from the ACGME Data Resource Books over a span of five academic years (2015-2020) was included. URM was defined as those who identified as Hispanic, Black, or Native American/Alaskan in concordance with AAMC definition. Chi square testing was used to compare the proportion of residency positions occupied by URM residents by self-identified race and ethnicity in radiation oncology to that of hematology and medical oncology, complex general surgical oncology, and all other specialties. Results: A total of 3,315 radiation oncology positions were identified over the study period, 2015 and 2020. 1,938 (58.5%) of radiation oncology residency positions were filled by residents who identified as White, 967 (29.2%) as Asian/ Pacific Islander, 126 (3.8%) as Hispanic, 120 (3.6%) as Black, 7 (0.2%) as Native American/ Alaskan, and 157 (4.7%) as Other. URM representation was 7.6% in total and was relatively stagnant, remaining between 7.3% and 8.0% across study years. Results of chi square comparative analysis demonstrated lower rates of representation in radiation oncology in comparison to hematology and medical oncology as well as all other specialties (Table). Conclusions: There is lack of racial and ethnic diversity in radiation-oncology residency training positions in the United States. Over the five-year study period, only 7.6% of trainees identified as URM. URMs have significantly lower rates of representation in radiation-oncology compared to hematology and medical oncology, and other specialties. Efforts to mitigate disparities require a multifaceted approach.

Results of chi square comparative analysis for representation in radiation oncology in comparison to hematology and medical oncology, surgical oncology, and all other specialties in total over study period. *denotes significance at P< 0.05 **denotes significance at P< 0.01.