Trastuzumab-containing therapies: Activity beyond disease progression in M.B.C.—A pivotal experience

Abstract

10788 Background: To evaluate Trastuzumab containing successive therapies activity in patients with overexpressing metastatic breast cancer (MBC). To determine the response rate (RR), time to progression (TTP) and overall survival (OS). Methods: Pivotal study of Trastuzumab (TZB) activity in HER-2 overexpressing MBC patients enrolled in our institution from 2000 to 2005. Results: 12 pts have been evaluated. Median age: 56; 8/12 postmenopausal,. 10/12 received adjuvant chemotherapy. Hormonal receptors: 8/12 positive, 4/12 negative. 8/12 pts had visceral disease. 11/12 had metastases in ≥ 2 locations. 5/12 pts received TZB as front line for MBC. Median previous lines: 2 (0–5). TZB was first time combined as follows: paclitaxel 7/12, docetaxel 4/12, (1/12 TZB alone). Asintomatic cardiac disfunction (LVEF reduction >10%) or CHF occurred in 1/12 pts (=CHF) after 46 months of TZB-treatment, with cardiac function progressively improving after standard medical care. RR for the 1st line (TZB containing): 11/12 (CR 3/12, PR 8/12), stable disease (S): 1/12, Clinical benefit (CB) 12/12, Median TTP 9.5 m (3–61+). 9/12 pts received a 2nd TZB containing therapy. RR for 2nd TZB-containing line: 4/8 (CR 0/8), SD 4/8, CB: 8/8; Median TTP: 8 months (3–14). All the 8/8 pts received a 3rd TZB- containing therapy. RR for 3rd TZB-containing line: 5/8 (CR 1/8), SD: 3/8, CB:8/8; Median TTP: 9 months (1–11). 4/8 pts have received a 4th or more TZB containing therapy with some long-lasting RR still presents at this time. Median overall survival is 33.5 months (9–61+). Conclusions: TZB-containing therapies beyond disease progression in MBC shows an interesting activity even in heavily pre-treated women. Small number of patients perhaps, do not allow to draw any final conclusion. No significant financial relationships to disclose.