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


Background: Colorectal polyps, especially adenomas, are known as precursors of colorectal carcinomas. This study was aimed at determining the prevalence and histopathologic characteristics of colonic polyps among Nigerians that underwent colonoscopy at the University of Ilorin Teaching Hospital, Ilorin, Nigeria. The authors also determined the polyp detection rate and adenoma detection rate.

Materials and Methods: This was a hospital-based cross-sectional study of all colonoscopy examinations performed at the University of Ilorin Teaching Hospital, Ilorin from March 2013 to September 2017. The endoscopy register was reviewed, and patients’ biodata, indications for colonoscopy and colonoscopic findings were recorded on a proforma. The histopathologic reports of the polyps were also retrieved and their diagnosis confirmed.

Results: A total of 289 patients had colonoscopy carried out on them. The age of the patients ranged from 14 to 90 years with a mean ±SD of 57.0 ± 15.3 years and a median age of 58 years. There were 178 (61.6%) males and 111 (38.4%) females giving a M:F ratio of 1.6:1. The indications for colonoscopy were rectal
bleeding 124 (42.9%); suspected colorectal cancer 67 (23.2%); abdominal pain 22 (7.6%); chronic diarrhea 18 (6.2%); surveillance colonoscopy 12 (4.2%); constipation 11 (3.8%); change in bowel habit 9 (3.1%); occult bleeding 6 (2.1%); others 20 (6.9%). Endoscopic findings were normal findings 89 (30.8%); hemorrhoids 88 (30.4%); colonic polyps 50 (17.3%); diverticulosis 34 (11.8%); rectal cancer 29 (10.0%); colon cancer 24 (8.3%); colitis 19 (6.6%); others 13 (4.5%). The findings were not mutually exclusive. The diagnostic yield was 69.2%. The overall polyp detection rate was 17.3%. Of the 50 patients with polyps, 33 (66.0%) were males (p = 0.481). The
adenoma detection rate was 4.8%.

Conclusion: The authors conclude that their observed polyp detection rate is consistent with the estimated rates for Africa. Rectal bleeding and adenomatous polyps were the commonest presentation and histopathologic finding, respectively.

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