The Relationships between Survivals and Early Salvage Androgen Deprivation Therapy for Non-Organ Confined Prostate Cancer after Radical Prostatectomy

Androgen deprivation therapy (ADT) is one salvage treatment used when prostate-specific antigen (PSA) recurs after radical prostatectomy (RP), especially in high-risk prostate cancer (PC) patients. However, the optimal timing for salvage ADT (SADT) is still unclear. In this study, we analyzed the efficacy of early SADT for non-organ confined PC. We investigated pathologically confirmed, non-organ confined PC patients who received SADT for PSA recurrence after RP. Patients with distant metastasis, those with lymph node involvement confirmed by lymph node dissection, and those who received neo-adjuvant or adjuvant therapy were excluded. Early SADT was defined as ADT initiated before PSA levels reached 0.5 ng/ml from the nadir PSA level after RP. Univariable and multivariable Cox regression analyses were performed for distant metastasis-free, PC-specific, and overall survival. Data from 345 patients were analyzed. The median follow-up duration was 82 months. The median PSA level was 10.9 ng/ml. Patients with T3b or T4 stage cancers represented 24.9% of the cohort; those with a Gleason score ≥9 represented 15.1%. The 10-year distant metastasis-free survival, PC-specific survival and overall survival were 87.1%, 92.0%, 80.9%, respectively. In univariable and multivariable Cox regression analyses, SADT that was initiated when PSA levels were less than 0.5 ng/mL was significantly associated with improved distant metastasis-free survival, PC-specific survival, and overall survival in non-organ confined PC. Early SADT initiated in patients with PSA levels <0.5 ng/mL was associated with increased distant metastasis-free survival, PC-specific survival, and overall survival in non-organ confined PC after RP.