First-line chemotherapy with docetaxel plus capecitabine followed by capecitabine or hormone maintenance therapy for the treatment of metastatic breast cancer patients

The primary aim of the present study was to evaluate whether maintenance therapy with capecitabine or hormone replacement therapy (HRT) results in improved progression-free survival (PFS) in metastatic breast cancer (MBC) patients who had previously achieved disease control with first-line docetaxel plus capecitabine (TX) chemotherapy. Seventy-nine metastatic breast cancer patients treated between January 2008 and June 2013 with TX chemotherapy were retrospectively analyzed. Following successful initial disease control by the combination chemotherapy, 39 patients received single-agent capecitabine maintenance therapy and 40 patients received HRT as maintenance therapy. The PFS time, objective response rate, clinical benefit rate and safety of the two groups were compared. The median PFS of the total cohort (n=79) was 11.0 months. Furthermore, the median PFS time of the capecitabine (n=39) and HRT groups (n=40) were 10.9 and 11.1 months, respectively (P=0.283). Compared with the PFS time of maintenance treatment only, single-agent capecitabine treatment following TX chemotherapy prolonged the PFS time by 6.8 months and HRT following TX chemotherapy prolonged PFS time by 5.8 months (P=0.551). Of the total cohort, 49 patients did not receive palliative endocrine therapy prior to chemotherapy, including 22 patients in the capecitabine maintenance group and 27 patients in the HRT maintenance group. The PFS time from the commencement of maintenance treatment was significantly different between the two groups, 6.1 months in the capecitabine group compared with 11.5 months in the HRT group (P=0.045). For the 30 patients who underwent palliative endocrine therapy prior to TX chemotherapy, the PFS times of the capecitabine and HRT maintenance treatment groups were 7.5 and 4.1 months, respectively (P=0.043). However, the occurrence of adverse events, such as hematological and gastrointestinal toxicity, as well as hand-foot syndrome, were not significantly different between the two groups. The current study indicated that single-agent capecitabine maintenance therapy may be a potential treatment strategy for MBC patients who responded to capecitabine-based chemotherapy. In particular, capecitabine may provide a more effective maintenance treatment duration compared with HRT for patients who had previously undergone first-line palliative HRT for MBC.