The present status of endocrine
therapy for
breast cancer was reviewed from the surgeon's point of view. Endocrine ablation
therapy, such as
oophorectomy,
adrenalectomy and
hypophysectomy, has been frequently used for the advanced
breast cancer patients. More recently, however, major endocrine ablation
therapy has been less the treatment of choice for advanced
breast cancer, because an
antiestrogen (
tamoxifen) which is less toxic has been prevailing in the treatment. It was shown that after the
breast cancer became refractory to
tamoxifen, the major endocrine ablation
therapy was effective particularly in ER (+)
cancers, irrespective of the response to the
antiestrogen. This suggests the significance of major endocrine ablation
therapy as a second line
therapy for advanced
breast cancer patients. The adjuvant endocrine and/or
chemotherapy for operable
breast cancer patients was reviewed, with special reference to the ovarian failure due to endocrine or chemotherapeutic agents. A prospective randomized study of endocrine and/or
chemotherapy for the adjuvant of
mastectomy stratified by the presence or absence of ER in
breast cancer tumors, has been performed in our hospital. Patients with ER (+) breast
cancers were divided into 3 groups: 1)
tamoxifen 20 mg/day for 2 years (in premenopausal status, after
oophorectomy), 2)
chemotherapy with
mitomycin C 20 mg/m2, iv, followed by administration of
cyclophosphamide 60 mg/m2, po, 3) combination of
tamoxifen and the
chemotherapy. The
chemotherapy alone or combination of
chemotherapy and
tamoxifen was given patients with ER (-)
cancers. At September, 1983, 422 patients took part in the trail, and the median follow-up period was 33 months (at least 9 months). The recurrence rate of the group treated with
antiestrogen alone was shown to be similar to that in other treatment groups in ER (+) cases.