The accuracy of mpMRI depends on the morphologic phenotype of the tumor. We showed that infiltrative growth is associated with lower signal on PSMA PET as well as reduced diffusion restriction on mpMRI. However, until now we do not understand why some tumors grow expansive while other have a more infiltrative growth. Therefore, we also do not know if we underestimate the tumor on mpMRI or see the delineation of the tumor well. This is a major limitation for successful targeted therapies in PCa.