Cancer is a disease of aging and, as the world's population ages, the number of older persons with cancer is increasing and will make up a growing share of the oncology population in virtually every country. Despite this, older patients remain vastly underrepresented in research that sets the standards for cancer treatments. Consequently, most of what we know about cancer therapeutics is based on clinical trials conducted in younger, healthier patients, and effective strategies to improve clinical trial participation of older adults with cancer remain sparse. For this systematic review, the authors evaluated published studies regarding barriers to participation and interventions to improve participation of older adults in cancer trials. The quality of the available evidence was low and, despite a literature describing multifaceted barriers, only one intervention study aimed to increase enrollment of older adults in trials. The findings starkly amplify the paucity of evidence‐based, effective strategies to improve participation of this underrepresented population in cancer trials. Within these limitations, the authors provide their opinion on how the current cancer research infrastructure must be modified to accommodate the needs of older patients. Several underused solutions are offered to expand clinical trials to include older adults with cancer. However, as currently constructed, these recommendations alone will not solve the evidence gap in geriatric oncology, and efforts are needed to meet older and frail adults where they are by expanding clinical trials designed specifically for this population and leveraging real‐world data.

PURPOSE: Limited tools exist to predict the risk of chemotherapy toxicity in older adults with early-stage breast cancer. METHODS: Patients of age ≥ 65 years with stage I-III breast cancer from 16 institutions treated with neoadjuvant or adjuvant chemotherapy were prospectively evaluated for geriatric and clinical features predictive of grade 3-5 chemotherapy toxicity. Logistic regression with best-subsets selection was used to identify and incorporate independent predictors of toxicity into a model with weighted variable scoring. Model performance was evaluated using area under the ROC curve (AUC) and goodness-of-fit statistics. The model was internally and externally validated. RESULTS: In 473 patients (283 in development and 190 in validation cohort), 46% developed grade 3-5 chemotherapy toxicities. Eight independent predictors were identified (each assigned weighted points): anthracycline use (1 point), stage II or III (3 points), planned treatment duration > 3 months (4 points), abnormal liver function (3 points), low hemoglobin (3 points), falls (4 points), limited walking (3 points), and lack of social support (3 points). We calculated risk scores for each patient and defined three risk groups: low (0-5 points), intermediate (6-11 points), or high (≥ 12 points). In the development cohort, the rates of grade 3-5 chemotherapy toxicity for these three groups were 19%, 54%, and 87%, respectively ( P < .01). In the validation cohort, the corresponding toxicity rates were 27%, 45%, and 76%. The AUC was 0.75 (95% CI, 0.70 to 0.81) in the development cohort and 0.69 (95% CI, 0.62 to 0.77) in the validation cohort. Risk groups were also associated with hospitalizations and reduced dose intensity ( P < .01). CONCLUSION: The Cancer and Aging Research Group-Breast Cancer (CARG-BC) score was developed and validated to predict grade 3-5 chemotherapy toxicity in older adults with early-stage breast cancer.

PURPOSE: Despite considerable research on the barriers to enrollment in cancer therapeutic trials, few studies have elicited barriers from the perspective of community physicians, who provide the majority of cancer care. The purpose of this study was to characterize barriers to and facilitators of cancer therapeutic trials as perceived by oncologists in community practices. METHODS: Twenty semistructured interviews were conducted with oncologists at six community sites affiliated with City of Hope National Medical Center from March to June 2018. Responses were recorded digitally and transcribed. Data were analyzed using qualitative content analysis. RESULTS: Of the 20 participants, 4 (20%) were women, 13 (65%) had > 10 years of practice experience, and 16 (80%) reported that < 5% of their patients were enrolled in a therapeutic trial. Participants identified four system-level barriers: lack of appropriate trials for community-based settings, insufficient infrastructure support, restrictive eligibility criteria, and financial limitations; three physician-level barriers: lack of awareness of available trials, lack of knowledge of trial details, and lack of time; and two patient-level barriers: patient burden and negative beliefs/attitudes toward research. Efforts aimed to increase trial availability, clinical trial support personnel, and physician knowledge were identified as major facilitators. CONCLUSION: Community oncologists face numerous complex, multifaceted barriers to cancer therapeutic trial enrollment. Although expanding clinical research beyond the academic setting allows access to a larger and more diverse patient population, increasing generalizability and relevance of trial findings, there remains a substantial need for new strategies to improve cancer research delivery in the community.