Primary combined androgen blockade in localized disease and its mechanism

In spite of clinical practice guidelines such as NCI-PDQ – in which primary androgen deprivation therapy (PADT) is not recommended as the primary treatment for localized prostate cancer – many patients have been treated with PADT. One of the reasons is that urologists themselves permit patients' desire because they know the effectiveness of PADT for some patients in their experiences. In this review we demonstrate basic mechanisms and the clinical efficacy of primary combined androgen blockade (PCAB) for localized or locally advanced prostate cancer. Then we discuss which patients are candidates for PCAB, and show that more than 30% of low- or intermediate-risk localized prostate cancers could be controlled in the long term with only PCAB. Short-term or intermittent PADT could not be recommended because of the possibilities of changing the character of the cancer cells by incomplete androgen ablation. We propose algorithms for the treatment of localized prostate cancer not only in low- and intermediate-risk groups but also in the high-risk group.

Key words: localized and locally advanced prostate cancer, primary androgen deprivation, primary combined androgen blockade, D'Amico risk grouping