Observational Study
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Jan 15, 2022; 14(1): 278-294
Published online Jan 15, 2022. doi: 10.4251/wjgo.v14.i1.278
Digestive cancer incidence and mortality among young adults worldwide in 2020: A population-based study
Jian Li
Jian Li, Department of General Surgery, The Third Hospital of Mianyang, The Mental Health Center of Sichuan, Mianyang 621000, Sichuan Province, China
Author contributions: The manuscript including tables and figures was drafted and revised by Li J.
Supported by the Scientific Research Projects of Health Commission of Mianyang City, No. 202012.
Institutional review board statement: The study was approved by the Ethics Committee of The Third Hospital of Mianyang.
Conflict-of-interest statement: There are no conflicts of interest to report.
Data sharing statement: All data are available in corresponding online databases.
STROBE statement: The author has read the STROBE Statement-checklist of items, and the manuscript was prepared and revised according to the STROBE Statement-checklist of items.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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: Jian Li, MM, Surgical Oncologist, Department of General Surgery, The Third Hospital of Mianyang, The Mental Health Center of Sichuan, No. 190 East Section of Jiannan Road, Youxian District, Mianyang 621000, Sichuan Province, China. 654747973@qq.com
Received: March 18, 2021
Peer-review started: March 18, 2021
First decision: July 3, 2021
Revised: July 4, 2021
Accepted: November 24, 2021
Article in press: October 24, 2021
Published online: January 15, 2022
Processing time: 298 Days and 10.9 Hours

Digestive cancer has traditionally been thought of as a disease that mainly occurs in elderly individuals, and it has been ignored in young adults by both patients and physicians.


To describe the worldwide profile of digestive cancer incidence, mortality and corresponding trends among 20–39-year-olds, with major patterns highlighted by age, sex, development level, and geographical region.


I performed a population-based study to quantify the burden of young adult digestive cancers worldwide. Global, regional, sex, and country-specific data estimates of the number of new cancer cases and cancer-associated deaths that occurred in 2020 were extracted from the GLOBOCAN Cancer Today database. To assess long-term trends in young adult digestive cancer, cancer incidence data and mortality data were obtained from the Cancer in Five Continents Plus database and the World Health Organization mortality database, respectively. The associations between the human development index (HDI) and digestive cancer burden in young adults were evaluated by linear regression analyses.


In 2020, there were an estimated 19292789 new cancer cases, resulting in 9958133 deaths worldwide, which equated to an age-standardized incidence rate (ASIR) of 5.16 and age-standardized mortality rate (ASMR) of 3.04, accounting for 12.24% of all new cancer cases and 25.26% of all cancer deaths occurring in young adults. The burden was disproportionally greater among males, with male: female ratios of 1.34 for incidence and 1.58 for mortality. The ASIRs were 2.1, 1.4, and 1.0 per 100000 people per year, whereas the ASMRs were 0.83, 1.1, and 0.62 per 100000 people per year for colorectal, liver, and gastric cancer, respectively. When assessed by geographical region and HDI levels, the cancer profile varied substantially, and a strong positive correlation between the mortality-to-incidence ratio of digestive cancer and HDI ranking was found (R2 = 0.7388, P < 0.001).


The most common digestive cancer types are colorectal, liver and gastric cancer. The global digestive cancer burden among young adults is greater among males and exhibits a positive association with socioeconomic status. The digestive cancer burden is heavy in young adults, reinforcing the need for primary and secondary prevention strategies.

Keywords: Digestive cancer, Incidence, Mortality, Young adults, GLOBOCAN, Mortality-to-incidence ratio

Core Tip: This study is the first to explore the global burden of digestive cancer among young adults. By assessing 6 major digestive cancer types, I provide up-to-date estimates across levels of sex, geographical region, and human development. Furthermore, this study investigates the long-term trends in digestive cancer in young adults, serving as the latest report to aid oncology studies and increase awareness of digestive cancer among this underserved subpopulation. Through continuous prevention, screening, and early detection programs, the digestive cancer burden in young adults can be reduced.