Lower Urinary Tract MCQs

Environmental factors are important in the pathogenesis of urothelial carcinoma and include cigarette smoking, various occupational carcinogens, and prior cyclophosphamide or radiation therapy. A family history of bladder cancer is a known risk factor. Squamous cell carcinoma is related to Schistosoma haematobium infections in areas where it is endemic. Cancers occurring in the setting of schistosoma infections arise in a background of chronic inflammation, which you will recall provides the 'soil' for the development of a number of different cancers. Other risk factors are aromatic amines, chlorinated hydrocarbons and polycyclic aromatic hydrocarbons including benzidine. Some genetic predispositions are also included. Reference : Robbins Basic Pathology, 10 th ed, Pg- 702

Given the recent travel history to Africa and work as a missionary, followed by hematuria, a Schistosoma infection is the most likely of the choices, as this parasite is found in Africa, it infects the bladder, and can present with hematuria. Transitional cell carcinoma of the bladder and renal cell carcinoma can cause hematuria with blood clots; however, he has no risk factors for either, and given his young age, they are unlikely. Membranous glomerulonephropathy does not cause hematuria, and postinfectious glomerulonephritis does cause hematuria, but the characteristic feature is red blood cell casts, and microscopic clots would not be formed. Reference : Robbins Basic Pathology, 10 th edition, Page- 702

The aromatic amines and azo dyes constitute another class of indirect-acting carcinogens. Before its carcinogenicity was recognized, β-naphthylamine and benzidine was responsible for a 50-fold increased incidence of bladder cancers in heavily exposed workers in the aniline dye and rubber industries. Reference: Robbins and Cotran Pathologic Basis of Diseases, 10 th ed, Pg: 230.

Two distinct precursor lesions of invasive urothelial carcinoma are recognized. The most common is a non invasive papillary tumour. The other precursor is carcinoma in situ (CIS), which is discussed later. In about one-half of patients with invasive bladder cancer, no precursor lesion is found; in such cases, it is presumed that the precursor lesion was overgrown by the high-grade invasive component. Adenocarcinomas of the bladder are rare. Carcinoma of the bladder is more common in men than in women, in industrialized than in developing nations, in urban than in rural dwellers. Reference: Robbins Basic Pathology, 10 th edition, Page- 702-703