Retrospective Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Dec 15, 2019; 11(12): 1151-1160
Published online Dec 15, 2019. doi: 10.4251/wjgo.v11.i12.1151
Asian Americans have better outcomes of non-metastatic gastric cancer compared to other United States racial groups: A secondary analysis from a randomized study
Omar Abdel-Rahman
Omar Abdel-Rahman, Department of Oncology, University of Alberta and Cross Cancer Institute, Edmonton, Alberta, Canada
Author contributions: Abdel-Rahman O made the conception, analysis and writing of the manuscript.
Institutional review board statement: As this manuscript is based on a publicly available database (project data sphere), IRB approval was not required.
Informed consent statement: As this manuscript is based on a publicly available database of de-identified records (project data sphere), informed consent was not required.
Conflict-of-interest statement: The author has no conflict of interest.
Data sharing statement: Dataset of the current study is available upon request from the online platform (Project Data Sphere): https://projectdatasphere.org/projectdatasphere/html/home
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/
Corresponding author: Omar Abdel-Rahman, MBChB, Academic Fellow, Department of Oncology, University of Alberta and Cross Cancer Institute, Edmonton, Alberta T2N4C2, Canada. omar.abdelsalam@ahs.ca
Telephone: +1-780-4328221 Fax: +1-780-4328888
Received: March 4, 2019
Peer-review started: March 4, 2019
First decision: July 31, 2019
Revised: September 18, 2019
Accepted: October 14, 2019
Article in press: October 14, 2019
Published online: December 15, 2019
ARTICLE HIGHLIGHTS
Research background

Gastric cancer behavior and outcomes might be different between patients living in Asian countries vs patients living in Western countries. It is not clear if these differences would persist between patients of Asian ancestry and patients of other racial subgroups within the multiethnic communities of North America.

Research motivation

This study hypothesizes that these differences will present within North American multiethnic communities.

Research objectives

To evaluate the impact of race on survival outcomes of non-metastatic gastric cancer patients in the United States.

Research methods

This is a secondary analysis of a randomized controlled trial (CALGB 80101 study) that evaluated two adjuvant chemoradiotherapy schedules following resection of non-metastatic gastric cancer. Kaplan-Meier analysis and log-rank testing were utilized to explore the overall and disease-free survival differences according to the race of the patients. Univariate and multivariate Cox regression analyses were then used to explore factors affecting overall and disease-free survival.

Research results

A total of 546 patients were included in the current analysis. Of which, 73.8% have white race (vs 12.8% black Americans and 8.2% Asian Americans). Using Kaplan-Meier analysis/log-rank testing, Asian Americans appear to have better overall and disease-free survival outcomes compared to other United States racial groups (White Americans, Black Americans and other racial groups) (P = 0.011; P = 0.010; respectively). Moreover, in an adjusted multivariate model, Asian American race seems to be associated with better overall and disease-free survival (hazard ratio: 0.438; 95%CI: 0.254-0.754), P = 0.003; hazard ratio: 0.460; 95%CI: 0.280-0.755, P = 0.002; respectively).

Research conclusions

Asian American patients with non-metastatic gastric cancer have better overall and disease-free survival compared to other racial groups in the United States. Further preclinical and clinical research is needed to clarify the reasons behind this observation.

Research perspectives

The findings of this study are thought-provoking for the potential biological mechanisms underlying this observation as well as the potential therapeutic implications of these findings.