Survival following primary androgen deprivation therapy for localized intermediate- or high-risk prostate cancer: comparison with the life expectancy of the age-matched normal population.

The representative guidelines do not recommend androgen deprivation therapy (ADT) as a primary treatment for localized prostate cancer. However, in clinical practice, the use of primary ADT for localized prostate cancer has been widespread, especially among older patients. We performed a retrospective review of the efficacy of primary ADT for localized prostate cancer and compared their outcomes with the life expectancy of the normal population. The study cohort consisted of 410 men diagnosed with localized intermediate- or high-risk prostate cancer over the period 1992-2012 at five institutions. All patients underwent ADT as a primary cancer therapy, and mean follow-up was 6.0 years. Their progression-free survival (PFS), cancer-specific survival (CSS), and overall survival (OS) rates were calculated. Patients' expected survival rates were estimated by the Hakulinen method. Multivariate analysis demonstrated that Gleason score ≥8 and cT3a were independent risk factors for all of PFS, CSS, and OS. In patients who have none or one of these risk factors, minimum OS rates were not inferior to the expected survival curves of the normal population. Meanwhile, in patients with both risk factors, the OS curve fell below the expected survival rates, especially after 6 years of follow-up. We conclude that primary ADT might be one of the therapeutic options for localized intermediate- and high-risk prostate cancer. However, for high-risk cases with Gleason score ≥8 and cT3a, the choice of primary ADT should be deliberated carefully because the OS of these cases was inferior to the expected survival, especially at a late time point.