First Large Scale Study of 50000 Asian Patients Shows Markedly Higher Cancer Risk in Those With Sclerosing Cholangitis. Colorectal Cancer Occurred in 9.1 Percent and Cholangiocarcinoma in 7.2 Percent

Professor Sang Hyoung Park of the Division of Gastroenterology at Asan Medical Center said “This study is significant in that it lays the foundation for developing Asia specific clinical guidelines.

▲ Professor Sang Hyoung Park of the Division of Gastroenterology at Asan Medical Center

Inflammatory bowel disease, represented primarily by Crohn disease and ulcerative colitis, is an intractable condition characterized by chronic inflammation of the gastrointestinal tract. Sclerosing cholangitis is a disease that causes chronic inflammation and fibrosis of the bile ducts and can progress to liver cirrhosis or liver failure. It is known to be closely associated with inflammatory bowel disease.

However, most previous studies on inflammatory bowel disease and sclerosing cholangitis have been conducted mainly in Western patient populations. In Asia, including Korea, the relatively small number of patients has limited the availability of large scale epidemiological studies to date.

A research team led by Professor Sang Hyoung Park of the Division of Gastroenterology at Asan Medical Center recently reported that, based on an analysis of approximately 50000 patients with inflammatory bowel disease from six Asian countries including Korea, Japan, and China, the prevalence of sclerosing cholangitis was five to seven times lower than in Western populations. However, when sclerosing cholangitis was present, the risks of developing colorectal cancer and cholangiocarcinoma increased substantially.

This study represents the first large scale epidemiological analysis to examine the prevalence and clinical course of sclerosing cholangitis among patients with inflammatory bowel disease in Asia. It is significant in that it scientifically demonstrates the importance of early diagnosis and management strategies tailored to the characteristics of Asian populations.

Professor Sang Hyoung Park’s team analyzed data from 51,314 patients with inflammatory bowel disease treated at 25 medical institutions across six Asian countries. Sclerosing cholangitis was identified in 474 patients, accounting for 0.92 percent of the total cohort. This prevalence is markedly lower than the 5 to 7 percent reported in Western populations. By disease type, sclerosing cholangitis occurred in 1.4 percent of patients with ulcerative colitis and 0.13 percent of those with Crohn disease.

Despite the lower prevalence among Asian patients with inflammatory bowel disease, the risks of cancer development and mortality were found to be high. In a long term follow up of 375 patients with inflammatory bowel disease complicated by sclerosing cholangitis over an average period of approximately 11 years, colorectal cancer developed in 9.1 percent of patients and cholangiocarcinoma in 7.2 percent. In addition, 24 percent progressed to severe liver disease such as liver cirrhosis or liver failure and ultimately required liver transplantation, while the overall mortality rate reached 16 percent.

However, recent advances in imaging technology have enabled earlier diagnosis, leading to improved patient outcomes. When the research team analyzed patients according to the time of diagnosis, those diagnosed after 2011 showed milder symptoms and better liver function test results compared with patients diagnosed before 2011. This improvement is attributed to the development of noninvasive imaging techniques such as magnetic resonance cholangiopancreatography, which have made early detection of sclerosing cholangitis possible.

Professor Sang Hyoung Park of the Division of Gastroenterology at Asan Medical Center stated, “This study provides important evidence for developing clinical guidelines tailored to patients with inflammatory bowel disease in Asia. Although the prevalence of sclerosing cholangitis itself is relatively low among Asian patients, the risk of cancer is high when the condition is present. Therefore, regular surveillance from the time of diagnosis is crucial to enable early detection and appropriate management.”

The study’s findings were recently published online in ‘Clinical Gastroenterology and Hepatology’, a leading international journal in the field of gastroenterology and hepatology.