Association between preradiation therapy prostate-specific antigen levels and radiation therapy failure after prostatectomy: a propensity score matched analysis

Purpose

We sought to determine the association between the pre-radiation therapy prostate-specific antigen (pre-RT PSA) 0.5 and RT failure in post-radical prostatectomy (post-RP) patients. Our study also investigated the prognostic factors for the failure of RT given concurrently with hormone therapy (HT) after RP.

Materials and methods

We retrospectively reviewed our institutional RP data from July 2004 to November 2021. Patients without concurrent hormone therapy were excluded. Propensity score matching was performed. Kaplan–Meier (KM) curve analysis was employed for RT failure-free survival, overall survival (OS), and cancer-specific survival (CSS). Cox regression analysis was used for the RT failure hazard ratio (HR).

Results

After propensity score matching, 193 patients were assigned to the pre-RT PSA ≥0.5 (high-P) arm, and 193 patients were assigned to the pre-RT PSA <0.5 (low-P) arm. There were no significant differences between the two arms after propensity score matching in terms of baseline characteristics and pathologic outcomes. High-P was associated with RT failure-free survival (P = 0.004), OS (P = 0.046), and CSS (P = 0.027). In a multi-variable Cox proportional hazards regression analysis, seminal vesicle invasion, lymph node invasion, the absence of prostatic intraepithelial neoplasia (PIN), and high-P were identified as significant risk factors for RT failure.

Conclusion

High-P was significantly unfavorable with RT failure-free survival, OS, and CSS in patients who underwent RT after radical prostatectomy with concurrent HT. Seminal vesicle invasion, lymph node invasion, and the absence of PIN were identified as significant prognostic factors for RT failure.