LAUSR

Micro‐Abstract In order to decide whether to administer radiation and a short or long course of androgen deprivation therapy in men with unfavorable intermediate‐risk prostate cancer, multiparametric magnetic resonance imaging could be considered when the prostate‐specific antigen is low (< 5 ng/mL) and the percentage core length high (> 70%) to identify occult Gleason score 8 or higher disease. Background: Some 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 Methods: The 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. Results: Fourteen 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). Conclusion: In 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.