[Efficacy of docetaxel for recurrent breast cancer: evaluation based on chemosensitivity test and clinical response]

We investigated the chemosensitivity of anticancer agents against primary (230 patients, 268 tumors) and recurrent breast cancer (40 patients, 51 tumors) using histoculture drug response assays (HDRA) of surgical specimens. Of the 40 recurrent breast cancer patients, 26 were pretreated with anthracycline. The efficacy of the agents was assessed according to an inhibition index of optical density detected by an ELISA reader. The inhibition rate of docetaxel against recurrent tumors was similar that against primary ones, although the rates of adriamycin, 5 fluorouracil, mitomycin and cisplatin against recurrent tumors were significantly lower than those against primary ones. The clinical response of docetaxel was also evaluated in ten patients with recurrent breast cancer. Of the ten patients with recurrent breast cancer, eight were pretreated with anthracycline, and seven showed a partial response. These results indicate that docetaxel is effective against recurrent breast cancer, even anthracycline-resistant breast cancer.