Prostate cancer (PC) is an entity that encompasses different types of tumors, including adenocarcinomas and non-adenocarcinomas. Adenocarcinomas and non-adenocarcinomas respond to, and therefore should be treated, with different treatments. Even within the adenocarcinomas, the lethality of tumors is highly variable, from low risk/indolent/non-life threatening to high risk/lethal. The inability to accurately predict the behavior of a particular cancer makes treatment decisions difficult and highly inexact. Elevated expression of prostate specific membrane antigen (PSMA) expression is a molecular hallmark of lethal prostate adenocarcinoma. Assessment of PSMA expression levels to predict the behavior of a particular cancer will be useful in the diagnosis and treatment of PC.