NEW research presented at the European Association for the Study of the Liver (EASL) Annual Congress 2024 investigated the familial risk of biliary tract cancer (BTC) and colorectal cancer (CRC) in patients with primary sclerosing cholangitis (PSC). PSC is a chronic liver disease often associated with a higher risk of BTC and CRC. It is well known that familial clustering of CRC takes place in the general population and in individuals with inflammatory bowel disease (IBD), however the familial clustering and cancer risk in individuals with PSC has not been uncovered.
This study, carried out by Erik von Seth, Karolinska University Hospital, Stockholm, Sweden, and team, aimed to assess this familial risk of CRC and BTC in a large population with PSC. The group included 1,594 patients with PSC and 15,940 comparators from the general population in Sweden, matched by age, sex, and geographical location. National Health Registries were used to identify first-degree relatives (FDRs) and individuals with CRC and BTC in the cohort. Logistic regression was used to calculate odds ratios (ORs) between PSC and their matched controls.
The team found that the prevalence of an FDR with CRC and BTC was similar in the group with PSC and the comparators (6.1% and 1.9% versus 6.4% and 1.4%, respectively). During a median follow-up time of 13.2 years, 5.0% (N=79) and 12.0% (N=191) of individuals with PSC were diagnosed with CRC or BTC. PSC with concomitant IBD had a higher likelihood of CRC than their healthy comparators (OR 5.1 (95% confidence interval [CI] 3.6-7.0). However, a family history of CRC was not associated with an increased risk of CRC in this group, RR 1.5 (95% C| 0.7-3.2). Having an FDR with CRC was associated with a higher likelihood of colectomy in individuals with PSC and IBD, RR 1.6 (95% Cl 1.2-2.2). The odds of BTC in PSC patients was higher compared to matched controls, OR 80.2 (95% Cl 54.4-123.1). Furthermore, familial occurrence of either CRC or BTC was not associated with higher risk of BTC. Having an FDR with CRC was associated with an increased risk of BTC in PSC.
This study demonstrated that a family history of CRC does not appear to increase the risk of CRC amongst PSC patients with concomitant IBD, but does increase the risk of colectomy, which may be explained by increased tendency for cancer preventative surgery. Those with an FDR with CRC had an increased risk of BTC in PSC, on top of already being high risk.
Reference
Von Seth et al. Familial risk of biliary tract cancer and colorectal cancer in patients with primary sclerosing cholangitis. Poster. EASL Annual Congress, 5-8 June 2024.
