Physician Perspectives on Reducing Curative Cancer Treatment Intensity for Populations Underrepresented in Clinical Trials

BACKGROUND: Historically, clinical trials involved adding novel agents to standard of care to improve survival. There has been a shift to an individualized approach with testing less intense treatment, particularly in breast cancer where risk of recurrence is low. Little is known about physician perspectives on delivering less intense treatment for patients who are not well represented in clinical trials. METHODS: Open-ended, individual qualitative interviews with medical oncologists explored their perspectives on trials that test less intense treatment for patients with cancer, with a focus on breast cancer. Interviews were audio-recorded and transcribed. Four independent coders utilized a content analysis approach to analyze transcripts using NVivo. Major themes and exemplary quotes were extracted. RESULTS: Of the 39 participating physicians, 61.5% felt comfortable extrapolating, 30.8% were hesitant, and 7.7% would not feel comfortable extrapolating trial outcomes to underrepresented populations. Facilitators of comfort included the sentiment that “biology is biology” (such that the cancer characteristics were what mattered), the strength of the evidence, inclusion of subset analysis on underrepresented populations, and prior experience making decisions with limited data. Barriers to extrapolation included potential harm over the patient’s lifetime, concerns about groups that had minimal participants, application to younger patients, and extending findings to diverse populations. Universally, broader inclusion in trials testing lowering chemotherapy was desired. CONCLUSIONS: The majority (92%) of physicians reported that they would de-implement treatment for patients poorly represented in clinical trials testing less treatment, while expressing concerns about applicability to specific subpopulations. Further work is needed to increase clinical trial representation of diverse populations to safely and effectively optimize treatment for patients with cancer. TRIAL REGISTRATION: NCT03248258