Multifocal Extraprostatic Extension of Prostate Cancer: A Third Subtype With Worse Prognosis Than Focal Prostate Cancer

Objectives: To investigate the prognostic utility of multifocal extraprostatic extension (EPE) on biochemical recurrence after radical prostatectomy. Methods: We conducted retrospective analysis of biochemical recurrence and prognostic pathologic variables in 673 men with stage pT3a/pT3b prostate cancer from 2000 to 2012. Extent of EPE on radical prostatectomy was divided into three groups: focal EPE (tumor dimension <0.8 mm), established (>= 0.8 mm), and multifocal (more than one focus of EPE <0.8 mm). Results: Type of EPE had significant effect on recurrence with progressively lower progression-free probability and higher recurrence probability from focal to established to multifocal. Multifocal and established tumors exhibited worse prognostic features and higher hazard ratio than focal. In multivariate analysis, established and multifocal were independent prognostic factors with the greatest adverse prognostic significance associated with multifocal. Conclusions: Identification of multifocal EPE provides important prognostic information associated with increased likelihood of recurrence compared to focal and established tumors.