Impact of adjuvant treatment for survival outcome in very elderly breast cancer patients (≥75 years)

Background: The optimal management of adjuvant breast cancer in very elderly women is controversial. There is a lack of data from clinical trials and thus a lack of guidelines. The aim of our study was to evaluate the impact of prognostic factors and therapeutic applications on survival.

Methods: This unicentric study included 452 breast cancer patients aged ≥75 years who received adjuvant therapy between 2000 and 2009. Reported treatment modalities were categorized as optimal or suboptimal standard. Factors with impact on survival (disease-free [DFS], breast cancer-specific [BCSS], and overall survival [OS]) were identified by log-rank test and Cox regression.

Results: Among 452 patients, 37 women (8.2%) refused any surgery. The rates of suboptimal standard treatment were higher for endocrine (12.8%), systemic (30.8%), and radiation therapy (18.8%). Using log-rank test standard radiotherapy, hormone receptor status, grading, tumor size, and nodal status were significantly related with DFS. The corresponding factors with an impact on BCSS were: standard endocrine therapy, hormone receptor, HER2, and nodal status. Age was significantly associated with OS.

Conclusion: Among this selected cohort, 46.7% of patients were treated with suboptimal standard. The general application of published guidelines showed only a marginal effect on BCSS. However, radiation (DFS) and endocrine therapy (BCSS) revealed a significant impact on survival outcomes. Both should be considered in treatment decisions with respect to patient's health status.