Meta-Analysis
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Apr 7, 2017; 23(13): 2435-2442
Published online Apr 7, 2017. doi: 10.3748/wjg.v23.i13.2435
What is the quantitative risk of gastric cancer in the first-degree relatives of patients? A meta-analysis
Mohammad Yaghoobi, Julia McNabb-Baltar, Raheleh Bijarchi, Richard H Hunt
Mohammad Yaghoobi, Richard H Hunt, Division of Gastroenterology, McMaster University, Hamilton, ON L8S 4K1, Canada
Julia McNabb-Baltar, Division of Gastroenterology, Hepatology and Endoscopy, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, United States
Raheleh Bijarchi, Division of Respirology, Department of Medicine, St. Michael’s Hospital, University of Toronto, Toronto, ON M5B 1W8, Canada
Richard H Hunt, Division of Gastroenterology, Farncombe Family Digestive Disease Research Institute, Hamilton, ON L8S 4K1, Canada
Author contributions: Yaghoobi M, McNabb-Baltar J and Bijarchi R were responsible for literature search, data gathering, and quality control; Yaghoobi M and Hunt RH were responsible for data analysis and preparation of manuscript.
Conflict-of-interest statement: The authors have no conflict of interest to declare.
Data sharing statement: No additional data is available.
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: Mohammad Yaghoobi, MD, MSc, AFS, FRCPC, Division of Gastroenterology, Division of Gastroenterology, McMaster University, Hamilton, ON L8S 4K1, Canada. yaghoob@mcmaster.ca
Telephone: +1-905-5259140
Received: October 30, 2016
Peer-review started: November 2, 2016
First decision: December 19, 2016
Revised: January 17, 2017
Accepted: March 15, 2017
Article in press: March 15, 2017
Published online: April 7, 2017
Abstract
AIM

To quantify the risk of gastric cancer in first-degree relatives of patients with the cancer.

METHODS

A comprehensive literature search was performed. Case-control trials comparing the frequency of a positive family history of gastric cancer in patients with gastric cancer, vs non-gastric cancer controls were retrieved. Studies with missed or non-extractable data, studies in children, abstracts, and duplicate publications were excluded. A meta-analysis of pooled odd ratios was performed using Review Manager 5.0.25. We performed subgroup analysis on Asian studies and a sensitivity analysis based on the quality of the studies, type of the outcome, sample size, and whether studies considered only first-degree relatives.

RESULTS

Thirty-two relevant studies out of 612 potential abstracts (n = 80690 individuals) were included. 19.0% of the patients and 10.9% of the controls had at least one relative with gastric cancer (P < 0.00001). The pooled relative risk for the development of gastric cancer in association with a positive family history was 2.35 (95%CI: 1.96-2.81). The Cochran Q test for heterogeneity was positive (P < 0.00001, I² = 92%). After excluding the three outlier studies with the highest relative risks, heterogeneity remained significant (P < 0.00001, I² = 90%). The result was not different among Asian studies as compared to others and remained robust in several sensitivity analyses. In the 26 studies which exclusively analysed the history of gastric cancer in first-degree relatives, the relative risk was 2.71 (95%CI: 2.08-3.53; P < 0.00001).

CONCLUSION

Individuals with a first-degree relative affected with gastric cancer have a risk of about 2.5-fold for the development of gastric cancer. This could be due to genetic or environmental factors. Screening and preventive strategies should be developed for this high-risk population.

Keywords: Gastric cancer, Risk, Relatives, Family history, Meta-analysis

Core tip: Several case-control studies have found a familial predisposition for gastric cancer. Most studies suggest that first-degree relatives of patients with gastric cancer are at higher risk. In this meta-analysis we aimed to quantify this risk by including case-control trials comparing the frequency of a positive family history of gastric cancer in patients with gastric cancer, vs non-gastric cancer controls were retrieved. We showed that the pooled relative risk for the development of gastric cancer in association with a positive family history was 2.35 (95%CI: 1.96-2.81). We concluded that the individuals with a first-degree relative affected with gastric cancer have a risk of about 2.5-fold for the development of gastric cancer. This could be due to genetic or environmental factors. Screening and preventive strategies should be developed for this high-risk population.