Many sorts of hormones such as estrogens have been reported as the factors accelerating the development of mammary cancer. In consequence, methods to block such accelerating factors in the advanced mammary cancer, that is, castration, adrenalectomy and hypophysectomy have been attempted as the therapy of the advanced mammary cancer. Since Atkins(1957)and Huggins and Bergenstal (1951)for the first time conducted the total adrenalectomy on patients with advanced or metastasizing mammary cancer, nearly 1, 000 instances of this kind of therapy have been reported in the world literature by the end of 1958. In September 1953, we commenced ovariectomy and total adrenalectomy as a therapy for the metastasizing mammary cancer, treating 34 cases by December 1958. The subjects of the operation were patients between 37 and 67 years of age with mammary cancer of advanced stage, the metastasis being demonstrated in the lymph gland, the skin, the liver, the lung, the bone and the brain. In these operations, ovariectomy or castration by irradiation was performed as the first step, and then adrenalectomy was conducted. Some clinical results are hereby reported. RESULTS