Evaluation of Estrogen Dependency of Human Breast Cancers : II. Clinical evaluation of tamoxifen in advanced primary and recurrent breast cancer

An antiestrogen (tamoxifen) was given to 17 patients with advanced breast cancer (both recurrent and primary cancers) during a period from June 1981 to September 1983. The response rate to the antiestrogen was 47.8% (8/17). Sixty percent (6/10) of patients with estrogen receptor positive (ER +) responded, compared with 16.7% (1/6) of patients with estrogen receptor negative (ER －). Forty percent of patients with soft tissue/lymph nodes involvement responded, compared with 27.2% in patients with bone metastasis, and 25.0% in patients with visceral involvement. Postmenopausal patients responded more than premenopausal ones. In recurrent cases, the response rate increased with the prolongation of disease free interval.

Eight out of 17 patients are still alive, and the longest survival case has been in a condition of partial response for 23 months so far. The mean survival period in 9 deaths was 13±9 months, with longest 32 months.

As shown here, some patients with advanced breast cancer respond very well to the therapy. From these results, we think the tamoxifen-containing endocrinotherapy in combination with chemotherapy is effective in treatment of · advanced cancer and its active application may enable patients to live longer in the rehabilitated situation.