Urinary Bladder Tumors in Southern Pakistan: A Histopathological Perspective

Background: this study intends to determine the frequency and clinicopatholog-ical characteristics of different types of bladder tumors, particularly transitional cellcarcinoma in cystoscopic bladder biopsies and resections in the local patient populationand compare these findings with local and international reports.methods: the study was conducted in the department of histopathology, sindhinstitute of urology and transplantation, karachi, pakistan from december 1996 todecember 2001. all patients with bladder growth who presented to the urology clinicof sindh institute of urology and transplantation (siut) during the study period andin whom a cystoscopy and bladder biopsy were performed, were included in thisstudy. the clinical and demographic data and the pathological diagnoses were retrievedfrom the original surgical biopsy reports. results: out of 500 patients, there were 421 (84.2%) males and 79 (15.8%)females. the mean age was 57.5±8.6 years (range: 4 to 82 years). among the primarybladder tumors, transitional cell carcinomas were the most common (94.3%) malignancy.a majority of these cases (62%) presented with superficial disease, whereas in 38%the disease was muscle-invasive at initial diagnosis. grading was possible in allexcept two cases, which contained only necrotic tumor tissue. a vast preponderanceof tumors (74.5%) were well-differentiated, while 25.5% were poorly-differentiated.conclusion: this study demonstrates that the vast preponderance of bladdertumors is of urothelial origin and malignant. benign tumors are very rare. the clini-copathological characteristics and frequency distribution of different types of bladdertumors in the local population are, in general, comparable to those reported in the worldliterature.