Observational Study
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jul 28, 2022; 28(28): 3695-3705
Published online Jul 28, 2022. doi: 10.3748/wjg.v28.i28.3695
Secular trends of intrahepatic cholangiocarcinoma in a high endemic area: A population-based study
Chun-Ru Lin, Yu-Kwang Lee, Chun-Ju Chiang, Ya-Wen Yang, Hung-Chuen Chang, San-Lin You
Chun-Ru Lin, School of Medicine, College of Medicine, Fu Jen Catholic University, New Taipei City 242008, Taiwan
Yu-Kwang Lee, Department of Surgery, National Taiwan University Hospital, Taipei 100229, Taiwan
Chun-Ju Chiang, Ya-Wen Yang, Graduate Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei 10055, Taiwan
Hung-Chuen Chang, Division of Gastroenterology, Department of Internal Medicine, Shin Kong Wu Ho-Su Memorial Hospital, Taipei 111045, Taiwan
San-Lin You, School of Medicine and Data Science Center, Fu Jen Catholic University, New Taipei City 242008, Taiwan
Author contributions: Lin CR, Lee YK, Chang HC and You SL conceived of and designed the study; Chiang CJ and You SL acquired the data; Lin CR, Lee YK and Yang YW performed the data analyses; Lin CR and You SL drafted the manuscript; Lin RC, Lee YK and You SL assisted in interpretation of the data; Lin RC, Lee YK, Chiang CJ, Yang YW and You SL critically revised the manuscript for important intellectual content.
Institutional review board statement: The study was reviewed and approved by Fu Jen Catholic University Institutional Review Board (No. C107099).
Informed consent statement: The data used in this study is from Taiwan Cancer Registry, a governmental database established by the Health Promotion Administration, Ministry of Health and Welfare, Taiwan. This study was approved by Taiwan Ministry of Health and Welfare, so the informed consent statement was not needed. The related authorization documents would be supplied in the supplement.
Conflict-of-interest statement: All authors report no relevant conflicts of interest for this article.
Data sharing statement: No additional data are available.
STROBE statement: The authors have read the STROBE statement, and manuscript was prepared and revised according to the STROBE statement.
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: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: San-Lin You, PhD, Assistant Professor, School of Medicine and Data Science Center, Fu Jen Catholic University, No. 510 Zhongzheng Road, Xinzhuang District, New Taipei City 242008, Taiwan. yousanlin@gmail.com
Received: April 6, 2022
Peer-review started: April 6, 2022
First decision: May 29, 2022
Revised: May 30, 2022
Accepted: June 30, 2022
Article in press: June 30, 2022
Published online: July 28, 2022

Intrahepatic cholangiocarcinoma (ICC) is one of the most aggressive malignancies. However, because of its scarcity there are limited population-based data available for investigations into its epidemiologic characteristics. In Taiwan, we have a national cancer registry database that can be used to evaluate the secular trends of ICC.


To evaluate secular trends of ICC according to age, sex, and risk factors in Taiwan.


In this population-based study, we used the national Taiwan Cancer Registry database. Age-standardized and relative percent changes in incidence rates were used to describe secular trends in incidence rates and sex ratios of ICC in Taiwan.


The age-standardized ICC incidence rate among males increased from 1.51 per 100000 in 1993-1997 to 4.07 per 100000 in 2013-2017 and among female from 1.73 per 100000 to 2.95 per 100000. The incidence in females tended to plateau after 2008-2012. For males, the ICC incidence increased as age increased. In the long-term incidence trend of ICC in females, the incidence of the four age groups (40-44, 45-49, 50-54 and 55-59 years) remained stable in different years; although, the incidence of the 60-64 group had a peak in 2003-2007, and the peak incidence of the 65-69 and 70-74 groups occurred in 2008-2012. Among males, beginning at the age of 65, there were increases in the incidence of ICC for the period of 2003-2017 as compared with females in the period of 2003-2017.


Increased incidence of ICC occurred in Taiwan over the past two decades. The increased incidence has progressively shifted toward younger people for both males and females.

Keywords: Intrahepatic cholangiocarcinoma, Incidence, Secular trend, Sex ratio, Risk factor

Core Tip: It is important to evaluate the secular trends of intrahepatic cholangiocarcinoma (ICC) incidence and to determine insightful etiological clues in a population with a high incidence of liver cancer. Using the national Taiwan Cancer Registry, we observed an increased incidence of ICC for both males and females. Our observations should be taken in the context of other studies conducted on secular trends of ICC.