Pathology and Pathogenesis of Bladder Tumors

Bladder tumors include epitheLial and mesenchymal types with epitheLial tumors much more common. Most of the epitheLial tumors are urotheLial carcinomas. The vast majority of urotheLial carcinomas are sporadic and several environmental risk factors have been estabLished. Genetic susceptibiLity also affects the individual's susceptibiLity to environmental risk factors. UrotheLial carcinomas are classified as noninvasive and invasive types, papillary and nonpapillary types, and low-grade and high-grade types. UrotheLial carcinomas harbor complex genetic changes and two major molecular pathways have been involved in their pathogenesis including fibroblastic growth factor 3 and TP53 pathways. The cLinical behavior of urotheLial carcinomas is mainly determined by their histological grade and stage however, certain biomarkers might be useful to predict their outcome and response to treatment.Besides urotheLial tumors, other less common bladder tumors include glandular tumors, squamous tumors, neuroendocrine tumors, mesenchymal tumors, and rare miscellaneous tumors. Some of these nonurotheLial tumors show distinct cLinicopathologic and genetic changes.