The risk of cholangiocarcinoma in patients with MASLD is not increased compared to the general population.

Background: Metabolic dysfunction-associated steatotic liver disease (MASLD) is increasing in prevalence globally. MASLD is associated with an increased rate of comorbidities, including cardiovascular disease, liver cirrhosis, and hepatocellular carcinoma (HCC). While the link between MASLD and HCC is well known, the potential association with biliary tract cancer, including cholangiocarcinoma (CCA) and gallbladder cancer (GBC), is less certain. To evaluate whether individuals with MASLD are at increased risk of developing CCA compared to the general population, we performed a nationwide cohort study investigating the longitudinal association between MASLD and CCA.

Methods: A retrospective cohort study was performed including all patients ≥18 years of age, diagnosed with MASLD, from 1^st of January 1987 to 31^st of December 2020, through the Swedish National Patient Register. For each patient with MASLD, ten individuals, matched to the MASLD patient on year of diagnosis, age, sex, and municipality were selected as reference individuals. The international Classification of Diseases (ICD) codes were used to define MASLD and incident CCA. Incidence rates were calculated, and regression analyses were performed.

Results: Out of the 11,940 exposed patients with MASLD, 11 developed CCA (0.1%) out of whom three were diagnosed with iCCA (0.03%), during a median follow-up time of  five years. Out of 112,537 reference individuals, 62 were diagnosed with CCA (0.3%), out of whom 15 were diagnosed with iCCA (0.01%). The rate of GBC was not higher compared to the reference population.

Conclusion: This large cohort study found a low incidence of CCA in patients with MASLD, comparable to the general population which can reassure clinicians and patients that no specific vigilance for CCA should be considered in MASLD patients at present.