The general objective of this retrospective and prospective study is to evaluate the diagnostic and prognostic role of a quantitative analysis of PET images with 18F-PSMA in all stages of the disease in patients with prostate cancer. To this end, both imaging parameters commonly used in clinical practice and the contribution of radiomic features will be investigated. The latter are quantitative features extracted from biomedical images, and are believed to be able to provide information, otherwise impossible to investigate, useful for the characterization of various pathologies. This methodology is very promising, but also recent and therefore little studied and standardized. Our objective is also to investigate how to optimize it from a purely methodological point of view.