Unfavorable Intermediate-Risk Prostate Cancer and the Odds of Upgrading to Gleason 8 or Higher at Prostatectomy

Abstract

BackgroundSome men with unfavorable intermediate-risk prostate cancer (PC) have occult disease with a Gleason score of 8 or higher unrecognized on biopsy because of a sampling error that would change management to long from short course androgen-deprivation therapy in conjunction with radiotherapy. Identifying such men could improve outcomes. Patients and MethodsThe study cohort consisted of 136 consecutive men with unfavorable intermediate-risk PC who underwent radical prostatectomy (RP) between 2005 and 2008. We performed logistic regression analysis to identify clinical factors associated with upgrading to a Gleason score of 8 or higher at RP. ResultsFourteen percent of the men were upgraded to a Gleason score of 8 or higher PC at RP. Both increasing prostate-specific antigen (PSA) (adjusted odds ratio, 1.98; 95% confidence interval, 1.19, 3.30; P = .01) and greatest percentage core length (GPC) (adjusted odds ratio, 1.11; 95% confidence interval, 1.03, 1.19; P < .01) were significantly associated with upgrading. A significant interaction between PSA and GPC was observed (P = .01). Specifically, men with low PSA (< 5 ng/mL) and those with larger GPC (> 70%) were significantly more likely to have a Gleason score of 8 or higher at RP compared to men with low PSA and GPC of 70% or less (35% vs. 0%; P = .01), whereas the same was not true among men with PSA levels ≥ 5 ng/mL (16% vs. 9%; P = .36). ConclusionIn men with unfavorable intermediate-risk PC, a multiparametric magnetic resonance imaging could be considered when the PSA is low and the percentage core length high to identify occult Gleason score 8 or higher disease and change management from short to long course androgen-deprivation therapy and radiotherapy.