The use of adjuvant endocrine breast cancer therapy in the oldest old

In order to report specifically on the use of adjuvant endocrine therapy (ET) in the oldest old breast cancer (BC) patients, we compared treatment patterns including drug compliance and persistence in a cohort of patients who were ≥ 80 years at diagnosis (n = 79) with those of "younger elderly" patients who were 60-79 years old (n = 358). The geriatric cohort more commonly declined the recommended ET (non-compliance: 13.0% vs. 4.5%, p = 0.011). Of the patients who initiated ET, only a minority of the older patients completed the planned therapy duration of five years (39.6% vs. 71.3%, p < 0.001). However, when applying strict criteria for non-persistence, this was found in comparable frequency (17.0% vs. 12.0%, p = 0.370). In older patients, medication was more often discontinued by the physician due to serious medical reasons independent of BC (17.0% vs. 4.7%, p = 0.003). Older women were treated by a general practitioner more often and not by an oncologist (54.4% vs. 23.9%, p < 0.001). Studies on compliance/persistence on cancer therapy in the oldest old demand a detailed follow-up of the patients and the consideration of principles of geriatric medicine. Efforts should be made to make sure that all physicians, but above all general practitioners, who are predominantly involved in the treatment of elderly BC patients, are provided with current knowledge and skills, as to ensure optimal patient management.