Variant Histology and Clinicopathological Features of Prostate Cancer in Men Younger than 50 Years Treated with Radical Prostatectomy.

PURPOSE: While prostate cancer is primarily a disease of older men, young age prostate cancer represents an important clinical subgroup which has not been adequately studied. We evaluated the histopathological features and associated clinical behavior of prostate cancer in a cohort of younger men treated with radical prostatectomy. MATERIALS AND METHODS: The study included 171 men younger than 50 years with prostate cancer who were treated with radical prostatectomy at an academic institution between 2001 and 2015. Comprehensive pathology review was performed. Clinical and followup data were obtained from a prospectively maintained institutional database. RESULTS: Median age was 43 years (range 38 to 49). Of the tumors 42% were Gleason score 3 + 3 and 45% were 3 + 4 while Gleason score 4 + 3, 4 + 4 and 4 + 5 disease comprised 10.5%, 0.5% and 1% of cases, respectively. Mucinous carcinoma (greater than 25% extracellular mucin), an uncommon histological variant which comprises 0.2% of prostate cancers, was noted in 11 of our cases (6%). A further 21 cases (12%) of acinar adenocarcinoma had a less than 25% mucinous component. Followup data were available on 156 men (91%). Biochemical recurrence developed in 12 patients (19%) but there was no documented postoperative metastasis or death from disease in the cohort. All cases of mucinous carcinoma were associated with favorable clinicopathological characteristics. CONCLUSIONS: Our findings provide additional evidence that younger men with prostate cancer who are treated with radical prostatectomy mostly have favorable disease characteristics and outcomes. While the histopathological features in our series were generally comparable to those of older onset carcinoma, our cohort was enriched for tumors with a mucinous phenotype. Correlation with molecular-genetic analysis in this subset of tumors may be valuable.