Overall survival of elderly patients with breast cancer is not related to breast-cancer specific survival: A single institution experience in Japan

BACKGROUND: As the aging population grows, the number of elderly breast cancer patients has rapidly increased especially in Japan; a suitable treatment for elderly patients, considering chronic comorbidities and treatment tolerance, is urgently needed. METHODS: In this retrospective study, 286 elderly breast cancer patients were investigated. Tumor characteristics and survival outcome were compared between 70-79-year-old and ≥ 80-year-old groups. Disease-free survival, overall survival, and breast cancer-specific survival were compared, and the effect of variables was analyzed statistically. For resectable cases, prognoses were compared based on treatment (standard therapy or undertreated). RESULTS: Tumor characteristics were similar between groups, but the Ki-67 labeling index tended to be higher in older patients. Elderly patients with resectable cancer tended to be undertreated. During the median 59-month follow-up period, overall survival was significantly worse in the ≥80-year-old than in the 70-79-year-old group (p < 0.001), but disease-free and breast cancer-specific survivals were equivalent. Recurrence or death event hazard rates tended to be lower in patients receiving standard treatment. CONCLUSIONS: Standard multidisciplinary treatment for breast cancer prevents recurrence and metastasis and tends to extend breast cancer-specific survival even in elderly patients.