[Evaluation of therapeutic regimens for taxane-resistant recurrent/metastatic breast cancer].

Taxanes (TX) were administered to 246 of 292 patients with recurrent/metastatic breast cancer (MBC) who were treated in Hiei Hospital between January 2001 and May 2006. Recently, TX has been increasingly prescribed for preoperative treatment and postoperative adjuvant therapy. To improve the prognosis of MBC, regimens effective for TX-resistant cancer patients should be developed. In this study, with respect to hormone receptor (HR) and Her 2/neu (HER 2), we retrospectively investigated whether our series responded to the regimens used after TX resistance was acquired. As post TX-resistance therapy (trastuzumab was combined in HER2-positive patients), 387 treatment regimens were administered to 166 patients. The following regimens achieved a response rate (patients achieving PR or CR/patients who could be evaluated) of 10% or more: combination therapy with TX and capecitabine (11/61, 18%), CPT-11 (10/57, 17.5%), vinorelbine (5/46, 10.9%), MFL-P (continuous treatment with MTX, 5-FU, LV, and CDDP) (12/47, 25.5%), and DMpC (5'-DFUR, MPA, CPA p.o.) (5/16, 31.2%). The latter 2 regimens achieved a high response rate,and some HR (-) and HER 2 (-) patients also responded to these regimens. In HR (+) or HER 2 (+) patients who responded to TX, survival was longer than that of non-responders. However, there was no difference in the treatment responsiveness of post-TX regimens between TX-responders and non-responders, suggesting the survival-prolonging effect of TX.