Current status of primary pharmacotherapy and future perspectives toward upfront therapy for metastatic hormone-sensitive prostate cancer

Since 1941, androgen deprivation therapy has been the primary treatment for metastatic hormone-sensitive prostate cancer. Androgen deprivation therapy consists of several regimens that vary according to therapeutic modality, as well as treatment schedule. Androgen deprivation therapy initially shows excellent antitumor effects, such as relief of cancer-related symptoms, tumor marker decline and tumor shrinking. However, most metastatic hormone-sensitive prostate cancer cases eventually develop castration resistance and become lethal. Taxanes, such as docetaxel and cabazitaxel, as well as novel androgen receptor-targeting agents, such as abiraterone acetate and enzalutamide, have emerged for metastatic castration-resistant prostate cancer. The concept and principle of primary therapy for metastatic hormone-sensitive prostate cancer has remained unchanged for decades. Recently, upfront docetaxel chemotherapy has been shown to prolong overall survival in men with metastatic hormone-sensitive prostate cancer, and would lead to a paradigm shift in primary pharmacotherapy for metastatic hormone-sensitive prostate cancer. This raises the possibility of upfront use of taxanes, as well as novel androgen receptor-targeting agents combined with androgen deprivation therapy. The present review summarizes the current status of primary pharmacotherapy for metastatic hormone-sensitive prostate cancer, and discusses future perspectives in this field.