Morphology of Colorectal Carcinoma among Nigerians: A 30-Year Review

ABSTRACT

Background: The incidence of colorectal carcinoma has been on the increase in the developing countries; including Nigeria; as a result of change in diet and adoption of western lifestyle. Objectives: The aim of this review is to highlight the prevalence; age and sex distribution; anatomical location; and morphological characteristics of colorectal carcinomas in Ilorin; Nigeria. Materials and Methods: This is a retrospective study of all cases of histologically diagnosed colorectal carcinoma in the University of Ilorin Teaching Hospital; Ilorin; Nigeria; over a 30-year period (January 1979-December 2008); using the departmental record and histological slides of the cases. Result: A total of 241 cases of colorectal carcinoma were reported; 144 cases (60) in males and 96 cases (40) in females with a male female ratio of 1.51. The peak age of occurrence for males was between 51 and 60 years; while that of the females was between 41 and 50 years. The malignancy was found in the rectum in 60.2of the cases; while the least affected site is the descending colon (1.2). The exophytic occluding masses were found in 82.2of the cases; and the most common histological type is adenocarcinoma (77.2) with well-; moderately; and poorly differentiated forms constituting 52.3; 32.8; and 14.9respectively. Of the 241 cases that were seen over the last 30 years; 93 cases (38.6) were seen in the last 5 years. Conclusion: Colorectal carcinoma is no longer a rare disease in Nigeria. The surge in the incidence reported in the last 5 years in this center calls for a pragmatic action in its control; with emphasize on colonoscopic screening for those with family history; and possibly making digital rectal examination a mandatory aspect of clinical examination; because most colorectal carcinomas are within the reach of examining finger