Objectives: We conducted a retrospective cohort study in cirrhotic patients to understand (i) the risk of developing hepatocellular carcinoma (HCC) after an initial negative screening computed tomography (CT) scan and its relationship with underlying etiology and (ii) the risk of extrahepatic cancers (EHCs).
Methods: Our cohort consisted of 952 cirrhotics who had at least one contrast-enhanced CT scan over a 5-year period from 1997 to 2002. We assessed their risk of HCC and EHC until the study closure (31 December 2007). Using data from the Indiana State Cancer Registry (ISCR), standardized incidence ratios (SIRs) were calculated for HCC and EHC.
Results: The cohort's follow-up was 4.7±3.0 years. The frequency of HCC at baseline and during follow-up was 6.9 and 7.2%, respectively. The 1-, 3-, and 5-year HCC incidence after an initial negative CT scan was 1.2, 4.4, and 7.8%, respectively. The 1-, 3-, and 5-year EHC incidence was 2.2, 4.5, and 6.8%, respectively. The most common EHCs were breast, lung, and lymphoma. Incidence of both HCC (P=0.016) and EHC (P=0.004) varied significantly by the etiology of underlying cirrhosis. The SIRs for HCC and EHC were 186 (95% confidence interval (CI) 140-238) and 1.83 (95% CI 1.36-2.36), respectively. Compared with adjusted ISCR data, cirrhosis due to alcohol (SIR 2.73, 95% CI 1.14-4.33) but not other etiologies had significantly higher incidence of EHC.
Conclusions: This study furthers our understanding of HCC and EHC risk in cirrhosis. If confirmed by other studies, these data will assist in developing optimal strategies for monitoring of cancer in individuals with cirrhosis.