We have identified five genomic subtypes of primary PCa that each involve at least two significantly co-occurring alterations: MAP3K7/CHD1/SPOP; ERG/PTEN/TP53; ATM/PARP1; BRCA1/TP53; BRCA2/RB1. These subtypes are highlighted in Table 1, along with mutual exclusivity of alterations between subtypes, and other alterations that co-occur broadly with aspects of multiple subtypes. The gene discussed is RB1; the disease is posterior cortical atrophy.