Poorer outcomes in cryptogenic hepatocellular carcinomas vs other aetiologies
Compared with viral hepatocellular carcinomas and those of other aetiologies, cryptogenic hepatocellular carcinomas tend to manifest at later stages and are associated with worse survival, according to a study presented at the 26th Conference of the Asian Pacific Association for the Study of the Liver (APASL 2017).
The retrospective cohort study involved 4,315 adult patients diagnosed with hepatocellular carcinoma at 3 different centers between 2004 and 2014. Patients were then stratified according to the aetiology of hepatocellular carcinoma: cryptogenic, alcohol only, hepatitis B virus and hepatitis C virus. Those with more than one aetiology were excluded.
Cryptogenic hepatocellular carcinomas were defined as those without a history of viral hepatitis or significant consumption of alcohol. Imaging techniques, biopsies and clinical assessments were used to confirm cirrhosis.
Less than half (45.8 percent) of all patients with cryptogenic hepatocellular carcinoma had cirrhosis. This was significantly different compared to the other aetiologies: 68.1 percent for hepatitis B virus, 75.5 percent for hepatitis C virus and 64.1 percent for alcohol only (p<0.001 for all) [APASL 2017, abstract PP0014].
Moreover, cryptogenic hepatocellular carcinoma patients also tended to be older compared to those of other aetiologies (67.2 years vs 58.3 years for hepatitis B virus, 63.0 years for hepatitis C virus and 63.2 years for alcohol only; p<0.001).
Cryptogenic tumours were more likely to be larger (p<0.001 for all) and have more metastases (p=0.002 for hepatitis B virus, p<0.001 for hepatitis C virus and p=0.029 for alcohol only), and less likely to meet the Milan criteria (p<0.001 for hepatitis B and C virus, and p=0.005 for alcohol only) compared with other aetiologies.
Furthermore, while they were just as likely to seek out curative treatment, patients with cryptogenic hepatocellular carcinoma had worse survival rates, as per the Model for End-Stage Liver Disease (p=0.001 for hepatitis C virus, p<0.001 for alcohol only).
Despite these, a cryptogenic aetiology for hepatocellular carcinoma was not independently correlated with poorer survival rates after adjustment.
The findings show that cryptogenic hepatocellular carcinomas tend to present at later ages, with more advanced tumours and worse survival rates. This may possibly be because of the lack of apparent cirrhosis, which in turn does not encourage vigilant screening for hepatocellular carcinoma.