[Prostate cancer--treatment of hormone independent cancer]

At the present time in Japan, the androgen ablation therapy, such as the surgical castration, estrogen therapy, antiandrogen therapy and LHRH agonist therapy, is mainly used for the treatment of advanced prostate cancer as well as for early prostate cancer. Ten to twenty percent of advanced prostate cancer do not respond to the initial endocrine therapy. The most of advanced prostate cancer relapse to androgen independent state within several years after the initial endocrine therapy. This characteristic of prostate cancers to develop resistance to androgen ablation therapy is the main problem in the treatment of prostate cancer. We surveyed the literatures regarding the treatments of the hormone independent prostate cancer. The results of bilateral adrenalectomy or antiandrogen therapy for patients who had relapsed to standard hormone therapy was disappointing. These data showed that the absence of testes and adrenals is not sufficient to stop the progression of the hormone independent cancer cells. Theoretically, the chemotherapeutic agents will be expected to be active agents for the hormone independent prostatic cancer. However, none of the products available are particularly active and the objective response rate is less than 10%. Therefore, the least toxic agents should be used. The treatment of painful metastasis in the terminal stage patients with hormone independent prostate cancer should be positively achieved. The external beam irradiation is useful for palliation of local bone pain of prostate cancer. Analgesics including morphine should be also positively used for the relief of pain in the terminal stage patients with prostate cancer.