Persistent Prostate-Specific Antigen After Radical Prostatectomy and Its Impact on Oncologic Outcomes

Abstract

BackgroundPersistent prostate-specific antigen (PSA) represents a poor prognostic factor for recurrence after radical prostatectomy (RP). ObjectiveTo investigate the impact of persistent PSA at 6wk after RP on long-term oncologic outcomes and to assess patient characteristics associated with persistent PSA. Design, setting, and participantsWithin a high-volume center database we identified patients who harbored persistent (≥0.1ng/ml) versus undetectable PSA (<0.1ng/ml) at 6wk after RP. Patients with neo- and/or adjuvant androgen-deprivation therapy (ADT) were excluded. Outcome measurements and statistical analysisLogistic regression models tested for prediction of persistent PSA. Kaplan–Meier analyses and Cox regression models tested the effect of persistent PSA on metastasis-free survival (MFS), overall survival (OS), and cancer-specific survival (CSS) rates. Propensity score matching (PSM) was performed to test the impact of salvage radiotherapy (SRT) on OS and CSS in patients with persistent PSA. Results and limitationsOf 11 604 identified patients, 8.8% (n=1025) harbored persistent PSA. At 15yr after RP, MFS, OS, and CSS were 53.0% versus 93.2% (p<0.001), 64.7% versus 81.2% (p<0.001), and 75.5% versus 96.2% (p<0.001) for persistent versus undetectable PSA, respectively. In multivariable Cox regression models, persistent PSA represented an independent predictor for metastasis (hazard ratio [HR]: 3.59, p<0.001), death (HR: 1.86, p<0.001), and cancer-specific death (HR: 3.15, p<0.001). SRT was associated with improved OS (HR: 0.37, p=0.02) and CSS (HR: 0.12, p<0.01) after 1:1 PSM. Main limitation is missing data on postoperative PSA and duration of salvage ADT. ConclusionsPersistent PSA is associated with worse oncologic outcome after RP, namely, metastasis, death, and cancer-specific death. In patients with persistent PSA, SRT resulted in improved OS and CSS. Patient summaryWe assessed the impact of persistent prostate-specific antigen (PSA) at 6wk after radical prostatectomy on oncologic outcomes. Early persistent PSA was associated with worse metastasis-free survival, overall survival, and cancer-specific survival. Salvage radiotherapy may result in a survival benefit in well-selected patients.