Risk Factors for Clinical Metastasis in Men Undergoing Radical Prostatectomy and Immediate Adjuvant Androgen Deprivation Therapy

Abstract

<b>Background:</b> Adjuvant androgen deprivation therapy (ADT) is a treatment option for prostate cancer(PC) patients after radical prostatectomy (RP). Although it can achieve a good progression-free survival rate,some patients still develop clinical metastasis. We here investigated risk factors of clinical metastasis in postprostatectomypatients who received immediate adjuvant ADT. Materials and <br/><b>Methods</b>: We identified 197 patientswith non-metastatic PC who underwent RP at our institution between 2000 and 2012, followed by adjuvantADT. The associations of various clinicopathologic factors with clinical metastasis (primary endpoint) andcancer-specific survival (secondary endpoint) were assessed. Multivariate analysis was conducted using a Coxproportional hazards model. Median follow-up was 87 months after RP. <br/><b>Results</b>: Nine (4.6%) patients developedclinical metastasis and six (3.0%) died from PC. Eight of nine metastatic patients had a pathologic Gleason score(GS) 9 and developed bone metastasis, while the remaining one had pathologic GS 7 and developed metastasisonly to para-aortic lymph nodes. On multivariate analyses, pathologic GS ≥9 and regional lymph node metastasis(pN1) were independent predictors of clinical metastasis and pathologic GS ≥9 was an independent predictor ofcancer-specific death. <br/><b>Conclusions</b>: Pathologic GS ≥9 and pN1 were independent predictors of clinical metastasisin post-prostatectomy patients who received immediate adjuvant ADT. Furthermore, pathologic GS ≥9 was anindispensable condition for bone metastasis, which may imply that patients with GS ≤8 on adjuvant ADT areunlikely to develop bone metastasis.