To study the benefit of trastuzumab in monotherapy or combined with different chemotherapeutic agents in the treatment for Her2+ metastatic breast cancer (MBC) patients after progression on prior trastuzumab therapy.

The clinical evolution of patients with Her2+ MBC diagnosed by IHC3+/FISH+, and treated with trastuzumab in several lines for the metastatic disease, has been studied retrospectively.

Twenty-four patients with Her2+ MBC were treated with several regimens containing trastuzumab alone or associated with chemotherapy and/or hormonotherapy. In the first line of treatment 12 RR (50%), 11 SD (45%), with a 95% clinical benefit, was observed. The patients received a second line obtaining 8 RR (33%), 15 SD (62%), with a clinical benefit of 95%. Seventeen patients were treated with a third line, 5 RR (29.4%) and 11 SD (64%) being observed, with a clinical benefit of 93%. Seven patients received a fourth line. In these, 2 RR and 4 SD, with a clinical benefit of 85%, were observed. Fifteen of the patients, with RE+, received hormonotherapy plus trastuzumab alone or with chemotherapy in one or more lines of treatment, obtaining 8 RR (53%) and 4 SD (26%), with a clinical benefit of 79%.

The association of herceptin with chemotherapy and/or hormonotherapy demonstrates a very active treatment in patients with Her2+ MBC. The benefit seems to continue in patients who already have received treatment with trastuzumab even in more than one regimen.