PURPOSE

We retrospectively evaluated the efficacy and safety of combination therapy of trastuzumab plus capecitabine in heavily pretreated patients with HER2-positive metastatic breast cancer (MBC).

METHODS

Patients with HER2-positive MBC who had been administered the combination therapy between July 2003 and July 2006 at the Cancer Institute Hospital, Tokyo, were retrospectively reviewed. Capecitabine (828 mg/m(2)) was given twice daily for 3 weeks followed by a 1-week rest period; this was repeated every 4 weeks. Trastuzumab was given at 4 mg/kg as an initial loading dose intravenously, followed by 2 mg/kg weekly. We investigated objective response rate (ORR), clinical benefit rate (CBR), and time-to-treatment failure (TTF) according to the Response Evaluation Criteria in Solid Tumors guidelines. Adverse events were graded according to the National Cancer Institute, Common Toxicity Criteria, version 3.0.

RESULTS

A total of 49 patients were assessed and median follow-up time of patients was 16.2 months (1.4-43.5 months). ORR was 16% (95% confidence interval: 7-30%) and CBR was 47% (95% confidence interval: 32-62%). Median TTF was 5.4 months. Common adverse effects were hand-foot syndrome, liver dysfunction, and bone marrow suppression. Grade 3 adverse events were observed in nine patients (18%). One patient (2%) suffered from symptomatic chronic heart failure, which improved after discontinuation of trastuzumab.

CONCLUSIONS

The combination therapy of trastuzumab plus capecitabine is effective and tolerable for heavily pretreated patients with HER2-positive MBC.