Twenty-Year Follow-Up of a Phase II Trial of Taxotere/Carboplatin/Herceptin in Patients With Metastatic HER2-Positive Breast Cancer.

Background: As the implementation of trastuzumab, several studies have investigated new agents and regimens to treat human epidermal growth factor 2-positive (HER2+) metastatic breast cancer (MBC). However, long-term survival analyses from HER2-targeted therapies are lacking. This is a 20-year follow-up study of a phase II trial that evaluated the activity and safety of docetaxel in combination with carboplatin and trastuzumab (TCH) in patients with HER2+ MBC.

Materials And Methods: This is a follow-up of a phase II, single-arm, open-label study. The primary objective was the activity from the combination of TCH in terms of response rate (RR). Secondary objectives included the activity from TCH in terms of response duration (RD), time to progression (TTP), overall survival (OS), and percent one-year survival.

Results: Between 11/1999 and 10/2002, 40 women were enrolled. Most patients (67.5%) had visceral metastasis on enrollment. After 2 decades and 3 months from first enrollment, there were 4 (10%) survivors (median follow-up of 3.2 years). The RR for complete response (CR) or partial response (PR) was 72.5%. The RR for CR was 42.5%. RD was 8 months. Median TTP was 10.8 months. Participants achieved a median OS of 39.8 months. Percent one-year survival was 92.5%.

Conclusion: A subset of patients (10%) receiving trastuzumab in the metastatic setting have achieved long-term survival beyond 20 years.