Cancer Risk in the Early Stages of Inflammatory Bowel Disease in Korean Patients: A Nationwide Population-based Study.
OBJECTIVE
The association between inflammatory bowel disease [IBD] and cancer remains poorly defined in Asian populations. Therefore, we conducted a nationwide population-based study to determine the cancer risk in Korean patients with IBD.


METHODS
Using the National Health Insurance claims data, we collected data on patients diagnosed with IBD (5595 Crohn's disease [CD] and 10 049 ulcerative colitis [UC]) from 2011 to 2014. Standardized incidence ratios [SIRs] of overall and site-specific cancers in IBD patients in comparison with the general population were calculated.


RESULTS
The overall cancer risk was higher in CD patients [SIR, 2.2; 95% confidence interval, 1.5-3.0 in men and 3.3; 2.4-4.5 in women] and UC patients [1.9; 1.6-2.3 in men and 1.9; 1.5-2.4 in women]. There were significantly increased risks for the following cancers: small bowel cancer [31.2; 3.8-112.8], colorectal cancer [CRC] [3.7; 1.6-7.2] and haematological cancer [4.0; 1.1-10.3] in men with CD; small bowel cancer [61.1; 7.4-220.6], CRC [4.7; 1.5-10.9], liver cancer [15.3; 5.6-33.2], pancreatic cancer [8.6; 1.0-31.0] and haematological cancer [11.0; 3.6-25.7] in women with CD; CRC [2.1; 1.3-3.3] and cancer of the prostate [3.5; 2.1-5.5], brain/central nervous system [6.1; 1.3-17.9] and thyroid [2.2; 1.1-3.9] in men with UC; and CRC [3.0; 1.5-5.3], cancer of the liver [4.4; 1.6-9.7] and cervix uteri [5.7; 2.4-11.1], and haematological cancer [3.5; 1.1-8.1] in women with UC. Women with CD had an increased risk of non-Hodgkin lymphoma [NHL] and leukaemia. Women with UC had an increased risk of NHL.


CONCLUSIONS
Korean patients with IBD are at increased risk for overall, intestinal and haematological cancer.
Division of Gastroenterology, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
Yoon Suk
YS
Jung
Department of Public Health, Graduate School, Yonsei University, Seoul, Republic of Korea.
Minkyung
M
Han
Department of Biostatistics, Graduate School of Public Health, Yonsei University, Seoul, Republic of Korea.
Sohee
S
Park
Department of Internal Medicine and Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Korea.
Won Ho
WH
Kim
Department of Internal Medicine and Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Korea.
Jae Hee
JH
Cheon
D000328:Adult; D001932:Brain Neoplasms / Q000209:etiology; D003093:Colitis, Ulcerative / Q000150:complications; D015179:Colorectal Neoplasms / Q000209:etiology; D003424:Crohn Disease / Q000150:complications; D005260:Female; D019337:Hematologic Neoplasms / Q000209:etiology; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000150:complications*; D007414:Intestinal Neoplasms / Q000209:etiology; D008113:Liver Neoplasms / Q000209:etiology; D008297:Male; D009369:Neoplasms / Q000209:etiology*; D011471:Prostatic Neoplasms / Q000209:etiology; D056910:Republic of Korea / Q000453:epidemiology; D012307:Risk Factors; D002583:Uterine Cervical Neoplasms / Q000209:etiology
Crohn’s disease; Korea; Ulcerative colitis; cancer; population-based