Clinicopathologic review of polyps biopsied at colonoscopy in Lagos, Nigeria

Abstract

IntroductionColorectal polyps are known precursors of colorectal cancers. The increase in utilization of colonoscopy in Nigeria has meant a rise in the recently reported incidence of these lesions. The aim of this study is to evaluate the clinicopathological profile of colorectal polyps biopsied during the inaugural 12 month period of colonoscopy from a private endoscopy suite in Nigeria.MethodsThis is a retrospective review of all the clients who had polyps diagnosed at colonoscopy over a 12 month period (August 2014 –July 2015) at a private endoscopy suite in Lagos, Nigeria. This analysis of prospectively collected data was performed using clinical information from the endoscopy logs and pathology database system of a private endoscopy suite based in Lagos, Nigeria.ResultsA total of 125 colonoscopies were carried out over the stated period. Of these, 14 individuals had a total of 18 polyps- 4 clients (28.6% of the persons with polyps) had two polyps each. The polyp detection rate was 11.2% while the polyp per colonoscopy rate was 14.4%. Of these clients, males were 10 in number; giving a male to female ratio of 2.5:1. Their ages ranged from 37 to 77 years (mean= 57.3 years). The presenting complaint at colonoscopy was hematochezia in 11 (78.6%), new onset constipation in 2 (14.2%) and peri-anal pain in 1 patient (7.1%). The polyps were distributed as follows; 2 (11.1%) in the ascending colon, 1 (5.6%) each in the transverse and descending colons, 8 (44.4%) in the sigmoid colon, 6(33.3%) located in the rectum. Hence, there was left sided (15 of 18= 83.3%) preponderance. Pathologically, tubular (adenomatous) polyp with or without low grade dysplastic changes was diagnosed in 6 of the 18 polyps (giving an adenoma detection rate of 4.8%), 4 (22.2%) were inflammatory polyps, 1 (5.6%) was malignant and another had the rare inflammatory fibroid polyp. Five (27.8%) of the specimens were reported as non-specific colitis.ConclusionThe study supports the present wisdom that polyps are clearly less prevalent in our environment when compared to the Western world. The increased prevalence with advancing age, in male subjects and of left sided lesions, is also in keeping with previous results from our environment. A case is also advanced for the increased deployment of endoscopy as a tool for the detection of these polyps and ultimately, the reduction of colorectal cancer in our population.

A Clinicopathological Review of Colonic Polyps in a Tertiary Hospital in North Central Nigeria

“…Some of the reported PDR from the latter include 35.5%, 45.8%, and 49.0% from France, Spain, and the United States, respectively [24][25][26]. Our ADR of 4.8% is the same as that obtained in Lagos, lower than the 6.8% obtained in Ile-Ife but higher than 2.9% obtained in Ghana [10,11,17]. These ADRs from African countries are, however, much lower than the 17.7%, 19.4%, and 31.0% obtained in France, Germany, and the United States, respectively [24,26,27].…”

“…The implication of this is that perhaps almost 50% of the polyps may be missed if flexible sigmoidoscopy is used to evaluate patients in our environment. This is more than the 33.3%, 22.2%, and 38.0% that was reported in Ile-Ife, Lagos, and the United States [10,11,35]. Colonoscopy rather than sigmoidoscopy may thus be a preferred screening tool in our environment.…”

“…Nigeria and other sub-Saharan African countries suggest that they may not be as rare as previously reported though the prevalence rates are still relatively low when compared to the rates reported among Caucasians and Asians [10][11][12][13][14][15][16][17]. Over a period May, 2012 [14].…”

“…The differences in the patient selection, geographical location, and sample size (289 versus 68) may account for the difference in the observed prevalence rate [12]. Oluyemi et al and Onyekwere et al in Lagos, South-western Nigeria obtained PDR of 11.2% and 6.8%, respectively [10,13]. A PDR of 1.0% was obtained by Obonna et al in Ondo, South-western Nigeria [16].…”

“…It was estimated that 30% of the Western population have colonic polyps, whereas lower rates (10-15%) were noted in Africa [8,9]. Recent studies in Nigeria and other sub-Saharan African countries have reported different prevalence rates of colonic polyps that appear to suggest that their occurrence in these countries may not be rare as previously noted [10][11][12][13][14][15][16][17]. Results from previous studies have also shown that colonic polyps are more common in men than in women and increase in frequency with increasing age in most of these studies.…”