Oral etoposide monotherapy for Chinese patients with metastatic breast cancer: Efficacy and tolerance regardless of heavy prior therapy.

1107 Background: Effective treatment options for metastatic breast cancer (MBC) patients heavily pretreated with chemotherapy are limited. Oral etopside 50mg/m2/daily for consecutive 21 days among 28 days has single-agent activity in these patients. However, the patients who have received heavy prior chemotherapy may have poor tolerance to prolonged oral etoposide for 21 days. Dosage and usage of oral etoposide remain uncertain. This study was designed as a prospective clinical trial to evaluate the efficacy and safety of short-term oral etoposide in Chinese patients with MBC who had received heavy prior therapy. METHODS Patients with measurable disease who had been previously treated with at least 2 chemotherapy regimens were treated with oral etoposide at 60 mg/m2 on day 1 to day 10 of a 21 day cycle. The primary end point was the progression free survival (PFS). The secondary end points were objective response rate (ORR), clinical benefit rate (CBR), overall survival (OS), and toxicity profiles. RESULTS Thirty-two patients received 230 cycles with a median of 6 cycles (range, 2 to 20 cycles) per patients. 8 patients (25%) had partial response (PR), 14 patients achieved stable disease (SD) and the ORR was 25%. 9 patients achieved SD for more than 24 weeks and CBR was 53%. Medium PFS was 5 months. The medium OS was 16 months (range, 3-51months). The patients achieved clinical benefit had longer survival time than those didn't (25.0 verses 11.0 months, p<.01). Among the 16 patients who have received more than 4 previous regimens treatment, 4 patients got PR, and 4 patients achieved SD for more than 24 weeks, which lead to a CBR of 50%. The most common hematologic adverse events were anemia (43.8%) and neutropenia (38.5%), whereas nausea/vomiting (75.0%) and alopecia (62.5%) were the most frequent non-hematologic toxicity. CONCLUSIONS These data demonstrate that oral etoposide given for 10 days of a 21-day cycle is effective and represents a well-tolerated treatment option for Chinese women with heavily pretreated MBC.