[Endocrine therapy of recurrent breast cancer]

The present status of endocrine therapy in the treatment of recurrent breast cancer was reviewed. Only one third of breast cancer responds to the endocrine therapy, and suitable patients should be selected the treatment. By means of estrogen receptor (ER), it is possible to select ER(-) patients who do not respond to therapy (response rate less than 10%) while 50-60% of ER(+) breast cancer patients respond to therapy. However, this is still unsatisfactory as 50-60% of recurrent breast cancer cases respond to combination chemotherapy. By adding to the ER status certain clinical parameters such as disease-free interval, metastatic site, and performance status, a better response would be obtained with endocrine therapy. The combination of chemotherapy with endocrine therapy would be expected to increase the probability of patient response. According to our prospective randomized trial, however, as well as other reported trials, the survival of patients treated with simultaneous chemo-endocrine therapy has not been prolonged as compared with those who had been treated sequentially with either therapy alone. This suggests that new therapeutic strategies will be necessary in the treatment of recurrent breast cancer.