Hepatitis B virus-related hepatocellular carcinoma in young adults: Efficacy of nationwide selective vaccination.

Aim: Hepatitis B vaccination in infancy was carried out in Japan only when the mother was persistently infected from 1986 to 2016. The aim of the present study was to elucidate the results of vaccination for the prevention of hepatocellular carcinoma in young adults.
Methods: We studied the number of patients who had liver cancer and died from 1976 to 2017 using a national database. Furthermore, we carried out a nationwide survey focusing on patients with hepatitis B virus-related hepatocellular carcinoma who were diagnosed when aged <40 years from 2007 to 2016.
Results: The national database showed that the number of deaths of patients aged <40 years decreased from 337 in 1986 to 61 in 2016. Among the 122 patients with hepatocellular carcinoma (HCC) who were registered in the survey, just three patients were born after the start of the vaccination in 1986. Liver cirrhosis, defined by a high Fib-4 index (≥3.25), was found in just 12.5% of the patients at the time of the survey. HCC was incidentally diagnosed in 85 of the 122 (69%) patients. More than 60% of the patients (54/88) were dead at the time of the study, which may be attributed to the delay in diagnosis.
Conclusions: Selective vaccination was effective for the prevention of hepatitis B virus-related HCC. In contrast, many young adults who missed the chance of hepatitis B vaccination and HCC surveillance developed HCC and died. Hepatitis B virus screening in young adults and careful follow up of infected patients are important to prevent HCC development.
(© 2019 The Japan Society of Hepatology.)