Geriatric determinants of curative radiotherapy scheme choice for older adults with breast cancer treatment compliance and tolerance: Results from the GERABEL study.

Introduction: Chronological and functional aging complicates care in older patients, and therapeutic decisions need to consider individual needs to minimise morbidity and mortality. Therapeutic decisions should be guided by a multidisciplinary geriatric assessment, allowing a complete assessment of physical and functional performance. In this context, the GERABEL study aimed to orientate the irradiation strategy based on a detailed oncogeriatric assessment in women more than 70 years old with breast cancer.

Materials and methods: This was a multicentre clinical trial conducted between January 2017 and June 2021. The oncogeriatric assessment comprised seven questionnaires (activities of daily living [ADL], instrumental ADL, Mini-Mental State Examination, mini Geriatric Depression Scale, Mini-Nutritional Assessment, Cumulative Illness Rating Scale-Geriatric, and Timed Up and Go) to determine a predictive score. Irradiation regimen was assigned according to oncogeriatric score: normofractionated - NF (score range, 160-200), hypofractionated - HF (score range, 159-120), or high-dose hypofractionated - HDHF (score ≤ 119). Endpoints were the overall tolerance to treatment, using the oncogeriatric score as a proxy at six months post-treatment, and compliance.

Results: After oncogeriatric assessment at baseline, 177 patients were treated with a NF regimen, 24 with a HF regimen, and four with a HDHF regimen. Tolerance was excellent in the three groups, as no decrease of more than 20 % in the oncogeriatric score was noted at six months post-treatment. More generally, 68 % and 73 % of patients reported an improvement of the oncogeriatric score at two months and six months post-treatment, respectively. Only four treatment interruptions were observed and quality-of-life was well-conserved. In the hypo fractionated groups, short-term toxicities were not increased and no impact was noted on compliance.

Discussion: Decision-making guidance for irradiation schemes in breast cancer according to oncogeriatric determinants was successful in older patients, who tolerated treatment well and, overall, had a preserved general condition.