Background/aims: To assess the risk of hepatic and extrahepatic malignancies in a large cohort of Swedish primary sclerosing cholangitis (PSC) patients compared with that of the general Swedish population.
Methods: The study cohort comprised 604 PSC patients identified between 1970 and 1998. Follow-up was provided through linkages to the Swedish Cancer and Death registries. Cumulative incidence of malignancies and standard incidence ratio were calculated with the incidence rates in the Swedish population, taking into account: sex, age and calendar year as comparison group.
Results: Median time of follow-up was 5.7 years (range 0-27.8). Seventy-nine percent had concomitant inflammatory bowel disease. The cause of death was cancer in 44%. The frequency of hepatobiliary malignancies was 13.3% (81/604). Thirty-seven percent (30/81) of all hepatobiliary malignancies were diagnosed less than 1 year after the diagnosis of PSC. The risk for hepatobiliary malignancy was increased 161 times, for colorectal carcinoma 10 times and for pancreatic carcinoma 14 times, compared with that of the general population.
Conclusions: In this national-based study including the largest cohort of PSC patients ever presented, the frequency of cholangiocarcinoma is 13%. The risk of hepatobiliary carcinoma is constant after the first year after PSC diagnosis with an incidence rate of 1.5% per year. The risk of pancreatic carcinoma is increased 14 times compared with the general Swedish population. These results are suggestive of an increased risk of pancreatic carcinoma in patients with PSC.