Retrospective Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Feb 28, 2015; 21(8): 2374-2380
Published online Feb 28, 2015. doi: 10.3748/wjg.v21.i8.2374
Retrospective study of colorectal cancer in Zimbabwe: Colonoscopic and clinical correlates
Leolin Katsidzira, Innocent Tichaona Gangaidzo, Munyaradzi Paul Mapingure, Jonathan Arthur Matenga
Leolin Katsidzira, Innocent Tichaona Gangaidzo, Jonathan Arthur Matenga, Department of Medicine, College of Health Sciences, University of Zimbabwe, Harare 00263, Zimbabwe
Munyaradzi Paul Mapingure, Research Support Centre, College of Health Sciences, University of Zimbabwe, Harare 00263, Zimbabwe
Author contributions: Katsidzira L was involved in study conception and design, data collection, analysis and interpretation and in writing the manuscript; Gangaidzo IT performed all the endoscopic procedures and was involved in study conception and design, data collection and interpretation, and in drafting, critical review and final approval of the manuscript; Mapingure MP was involved in data analysis and critical revision of the manuscript; Matenga JA was involved in study conception and design, critical revision of the manuscript and final approval of the article.
Supported by Grants from Wellcome Trust through the Southern African Consortium on Research Excellence.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Dr. Leolin Katsidzira, Department of Medicine, College of Health Sciences, University of Zimbabwe, PO Box A178, Avondale, Harare 00263, Zimbabwe. lkatsidzira@hotmail.com
Telephone: +263-4-731000 Fax: +263-4-251017
Received: August 3, 2014
Peer-review started: August 3, 2014
First decision: August 27, 2014
Revised: September 25, 2014
Accepted: December 1, 2014
Article in press: December 1, 2014
Published online: February 28, 2015
Processing time: 209 Days and 16.4 Hours
Abstract

AIM: To compare differences in the frequency of colorectal cancer at colonoscopy in Zimbabwe according to ethnicity.

METHODS: All lower gastrointestinal endoscopic procedures performed between January 2006 and December 2011 at a gastroenterology clinic in Harare, Zimbabwe were reviewed. The demographic characteristics, clinical indications, differences in bowel preparation and the endoscopic and histological diagnoses were compared between different ethnic groups with emphasis on colorectal cancer. The clinical and demographic characteristics and the endoscopic findings were compared using the student t-test and the χ2 test, while the clinical indications associated with a diagnosis of colorectal cancer were determined by logistic regression.

RESULTS: All colonoscopies and sigmoidoscopies performed in 1236 Caucasians, 460 black Africans and 109 Asians were analysed. Colorectal cancer was diagnosed more frequently in the black African patients compared to Caucasians or Asians (10% vs 3%, 10% vs 2%, P < 0.001). However, polyps were less common among black Africans (5%) compared to both Caucasians (8%) and Asians (9%) (P = 0.03). Among patients with colorectal cancer, black Africans tended to be younger than Caucasians, who were over-represented in the oldest age category; 32 % vs 2% were less than 50 years and 41% vs 78% were older than 60 years (P < 0.001). Anaemia and weight loss were associated with colorectal cancer in both black African [odds ratio (OR): 2.73 (95%CI: 1.33-5.61) and 3.09 (1.35-7.07)] and Caucasian patients [OR: 6.65 (95%CI: 2.93-15.09) and 3.47 (1.52-7.94)].

CONCLUSION: The likelihood of diagnosing colorectal cancer in patients referred for colonoscopy in Zimbabwe is at least as likely among black Africans as it is among Caucasians.

Keywords: Colorectal cancer; Africa; Epidemiology; Colonoscopy; Adenomatous polyps; Diverticulosis; Colitis

Core tip: Colorectal cancer is traditionally regarded as rare in Africa. Consequently, the index of suspicion among medical practitioners is low, potentially resulting in delayed or missed diagnoses. This article demonstrates that colorectal cancer is as frequent a finding in Africans presenting for colonoscopy in Zimbabwe as it is among Caucasians. These African patients are often younger, implying that investigations for colorectal cancer among should be instituted in all patients in the right clinical context regardless of age. The decision to investigate should not be influenced by ethnicity or age in this population.