Risk factors for cancer in patients with primary biliary cholangitis and autoimmune hepatitis and primary biliary cholangitis overlap syndrome

Primary biliary cholangitis (PBC) and autoimmune hepatitis (AIH) and PBC overlap syndrome (AIH/PBC) have been associated with a higher risk of hepatocellular carcinoma (HCC) and extra-hepatic malignancy (EHM). This study aims to assess potential risk factors associated with cancer development in PBC and AIH/PBC.The Brazilian Cholestasis Study Group database was reviewed to compare clinical and laboratory features of PBC patients with HCC and EHM with those without cancer.Among the 752 PBC patients enrolled, 64 of them with AIH/PBC, 87 cancers were identified in 72 patients, including 20 cases of HCC and 67 of EHM. Patients with HCC had a higher prevalence of cirrhosis (95% vs. 32.5% of those subjects without cancer, p≤0.001), smoking (55% vs. 12.3%, p≤0.001), CREST syndrome (30% vs 7.6%, p=0.003) and prior azathioprine (30% vs 8%, p= 0.005) and prednisone (35% vs 14%, p= 0.018) use, whereas patients with EHM had a higher prevalence of smoking (42.3% vs 12.4% of those subjects without cancer, p= <0.001), AMA positivity (96.6% vs 80.1%, p≤0.001), azathioprine therapy (21% vs 7.9%, p= 0.01) and concurrent other autoimmune diseases. In multivariate analysis, cirrhosis, obesity and prior azathioprine therapy were independent risk factors for HCC, while Sjogren syndrome and psoriasis were associated with EHM. Fibrates reduced EHM risk.The prevalence of EHM is higher when compared to HCC in PBC patients. Cirrhosis, obesity, prior azathioprine use, and concurrent autoimmune diseases were significantly associated with cancer in PBC.