A descriptive study of bladder tumors in Benin City, Nigeria: An analysis of histopathological patterns

Abstract

Aims and Objectives: This study is aimed at determining the frequency and histopathological patterns including grading and staging of bladder tumors as seen in University of Benin Teaching Hospital, Benin City, Nigeria and to compare with similar research works elsewhere. Materials and Methods: A retrospective study of all data of surgical excision and cystoscopic bladder biopsies received over a 10-year period (2003-2012) at the Department of Histopathology, University of Benin Teaching Hospital, Benin City, Nigeria. Histological criteria published by the World Health Organization/International Society of Urological Pathology were used for the diagnosis and grading of these tumors. Results: A total of 75 bladder lesions were received in the Pathology Department. Of these, 64% were males and 36% were females giving a male to female ratio of 1.7:1.0. The peak and mean age incidence of urothelial bladder lesions was 60-69 years and 54.9 years ± 8.6 standard deviation, respectively. Bladder tumors accounted for 74.7% of all bladder lesions. Fifty-one (68%) cases out of 75 lesions were malignant tumors. Transitional cell carcinoma (TCC) was the most commonly encountered histological pattern accounting for 64.7% of bladder cancer. High grade papillary urothelial carcinoma was the most common tumor grade accounting for 51.4%. Only 40.6% cases were urothelial confined carcinoma (PTa) while 29.7% each accounted for lamina propria (PT1) and muscle (PT2) invasive carcinoma. Conclusion: Bladder tumors are more commonly encountered in males with the majority of cases occurring in the 7 th decade. Both high-grade TCC in stage (PT2) and low-grade carcinomas stage (PTa) were relatively common patterns seen in this study.