International Journal of Research in Medical Sciences | May 2020 | Vol 8 | Issue 5 Page 1 International Journal of Research in Medical Sciences Sanni DA et al. Int J Res Med Sci. 2020 May;8(5):xxx-xxx www.msjonline.org pISSN 2320-6071 | eISSN 2320-6012 Original Research Article Histopathology of bladder carcinomas: an eight year retrospective study at Lagos state university teaching hospital, Ikeja, Nigeria Daniel A. Sanni 1 *, Oluwaseun O. William 1 , Sunday S. Soyemi 1 , Abimbola A. Abolarinwa 2 , Abiodun O. Popoola 3 INTRODUCTION Bladder cancer is the 10th most common cancer worldwide, the 6 th most commonly occurring cancer in men and the 17 th most commonly occurring cancer in women. 1 There were almost 550,000 new cases and 200,000 deaths globally in 2018. 1 In both sexes, the highest incidence rates of bladder cancer are observed in Europe and North America. 2 Bladder cancer is a significant health care burden in developed countries due to its high incidence rates. It is estimated that bladder cancer costs €4.9 billion in the European Union in 2012. 3 Accurate epidemiological data about the incidence and mortality of bladder cancer are unavailable for regions with lower development indices. 4 However, the highest mortality rates have been recorded in Western Asia and Northern Africa. 5,6 Bladder cancer formed 6.4% of all malignancies seen in Kano in Northern Nigeria compared to 1.25% in Ibadan, South west Nigeria. 7,8 The exact causes of bladder cancer are unknown; however, there are several associated risk factors. These include environmental factors, such as smoking and exposure to certain industrial chemicals (aromatic amines, polycyclic aromatic hydrocarbons and chlorinated hydrocarbons). 9 Chronic bladder inflammation due to Schistosomia haematobium infection, chemotherapeutic agents, analgesic abuse and 1 Department of Pathology and Forensic Medicine, 2 Department of Surgery, 3 Department of Radiology, Lagos State University Teaching Hospital, Ikeja, Lagos State, Nigeria Received: 10 March 2020 Accepted: 16 March 2020 *Correspondence: Dr. Daniel A. Sanni, E-mail: daniel.sanni@lasucom.edu.ng Copyright: © the author(s), publisher and licensee Medip Academy. This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. ABSTRACT Background: This study was undertaken to evaluate the histological types, frequency, age and sex distribution of bladder carcinoma in Lagos State University Teaching Hospital (LASUTH), Ikeja, Lagos state. This study aims to classify bladder carcinoma in this centre according to the World Health Organisation/ International Society of Urological Pathology. Methods: An eight-year retrospective study of all bladder carcinomas specimens that were sent to the department of Pathology and Forensic Medicine, LASUTH between 1st January, 2011 and 31st December, 2018 was done. Relevant data consisting of the age and sex distributions as well as histopathological types were extracted from the departmental information system and filed documents. The data was analysed using the IBM-SPSS version 25.0. Results: There were 87 cases of bladder tumours, out of which 55 (63.2%) were bladder carcinomas. The mean age at diagnosis of bladder carcinomas was 56.9±13.9 years. Sex distribution has male to female ratio of 1: 1. Urothelial carcinoma predominates as the most common histological type. Conclusions: Bladder carcinoma presents most frequently at the 5th decade of life, with a slight male preponderance. Keywords: Age at diagnosis, Bladder carcinoma, Histological type DOI: http://dx.doi.org/10.18203/2320-6012.ijrms20201489