High incidence of high-grade prostatic intraepithelial neoplasia and prostatic adenocarcinoma—in the development of both of which, AR plays a critical role—in cystoprostatectomy specimens undergone for bladder urothelial carcinoma (e.g., 24.4% for the latter in a meta-analysis involving 13,140 patients [57]) may also support the presence of common tumorigenesis signals between these two malignancies. This evidence concerns the gene AR and bladder transitional cell carcinoma.