[A Retrospective Analysis on Comparative Treatment Results for Breast Cancer between Elderly Women Aged 70 and More Than 80 Years].

This study compared the treatment results of over 80-year-old(O-80) 54 and 157 septuagenarian(70s)women with breast cancer(BC)from 1996 to 2015, to clarify the best treatment option for O-80BC patients. No differences were observed in the stages and subtypes. More than 70% of women in both groups underwent breast-conserving surgery(BCS), and 48.1% and 12.1% of O-80BC and 70sBC patients did not undergo axillary dissection, respectively. About 3.2% and 18.5% of 70sBC and O-80BC patients did not receive adjuvant therapies, respectively. Most ER-positive patients in both groups received endocrine therapy. Most patients in both groups received no intravenous chemotherapy; however, oral chemotherapy was administered in 80.3% of 70sBC and 64.8% of O-80BC patients. Approximately 75.2% of 70sBC and 11.1% of O-80BC patients received post-surgical radiotherapy(RT). No differences in both relapse-free survival and overall survival (OS)rates were observed between the 2 groups. Breast cancer-related death(57.1%)and natural death from old age (57.1%)were the most commonly observed cause of death in the 70sBC and O-80BC groups, respectively. Multivariate analyses on OS demonstrated that BCS and intravenous chemotherapy were significantly associated with poor prognosis and RT was significantly associated with better prognosis in 70sBC group, whereas BCS was significantly associated with better prognosis in O-80BC group. In conclusion, surgery, especially BCS, plays an important role in the primary treatment of O- 80BC patients; however, axillary dissection, RT, endocrine therapy, and chemotherapy cannot be performed.