Prolonged clinical benefit from the maintenance hormone therapy inpatients with metastatic breast cancer

Objective: We investigated the efficacy of maintenance hormone therapy (MHT), which was given to hormone positive metastatic breast cancer (MBC) patients in non-progression status to the previous chemotherapy. Methods: This study retrospectively analyzed 76 MBC patients who had been treated with MHT from 2006 to 2010 at a single institute. Results: For the 76 patients reviewed, the median progression free survival (PFS) to MHT was 14.4 months (95% CI,11.6-17.3). Prolonged PFS was associated with less previous palliative chemotherapy, fewer metastatic sites, and the absence of visceral metastasis in univariate analysis. Multivariate analysis showed that only the number of previous palliative chemotherapy (HR 1.73, 95% CI, 1.00-2.98; P=0.04) remained as a significant variable. MHT was generally well tolerated. Conclusions: MHT showed considerable efficacy and tolerability in this study. Further randomized prospective study is warranted.