Prevalence and risk factors of contralateral extraprostatic extension in men undergoing radical prostatectomy for unilateral disease at biopsy: A global multi-institutional experience

Abstract

Introduction: We assessed the incidence of contralateral prostate cancer (cPCa), contralateral EPE (cEPE) and contralateral positive surgical margins (cPSM) in patients diagnosed preoperatively with unilateral prostate cancer and evaluated risk factors predictive of contralateral disease extension.Methods: The occurrence of cPCa, cEPE and cPSM and the sidespecific nerve-sparing technique performed were collected postoperatively from 327 men diagnosed with unilateral prostate cancer at biopsy. Parameters, such as the localization, proportion, and percentage of cancer in positive cores, were prospectively collected.Results: Overall, 50.5% of patients had bilateral disease, and were at higher risk when associated with a positive biopsy core at the apex (p = 0.016). The overall incidence of ipsilateral EPE and cEPE were 21.4% and 3.4%, respectively (p < 0.001). Compared to cPCa, ipsilateral disease was at an almost 4-fold higher risk of extending out of the prostate (p < 0.001). None of the criteria tested were identified as useful predictors for cEPE. The low incidence of cEPE in our cohort could limit our ability to detect significance. The overall incidence of ipsilateral PSM and cPSM were 15.3% and 5.8%, respectively (p < 0.001). More aggressive nerve-sparing was not associated with a higher incidence of PSM. Prostate sides selected for more aggressive nerve-sparing were associated with younger patients (p < 0.001), a smaller prostate (p = 0.006), and a lower percentage of cancer in biopsy material (p = 0.008).Conclusion: Although the risk of cPCa is high in patients diagnosed with unilateral prostate cancer at biopsy, the risk of cEPE and cPSM is low, yet not insignificant. Contralateral aggressive nervesparing should be used with caution and should not compromise oncological outcome.