RB1 and Familial prostate cancer: In contrast, mestatic noncastrate resistant prostate cancers displayed a frequency of the major genetic alterations similar to that observed in localized prostate cancers, with the exception of a moderate increase of alterations of PTEN (18% vs. 12%), RB1 (7% vs. 2%), APC (14% vs. 4%), KMT2C (9% vs. 4%), and CDK2 (6% vs. 4%); the frequency of AR alterations remained low in these tumors (4%) and much lower than in mCRPC (54%).