see also:

• neoplasia / cancer / tumours
• cirrhosis
• hepatitis

• globally, liver cancer is the 5th most common cancer in men, and the 7th most common in women
• 80-90% have cirrhosis as the main risk factor
• it is rare < 40 years age, and reaches a peak at 70 years age
• hepatocellular carcinoma due to HCV is the fastest rising cause of cancer-related death in the Western world, with incidence in USA tripling over past 20 years while 5yr survival rate remains below 12%.
• surveillance using alpha fetoprotein levels (20ng/ml cutoff gives sensitivity only 25-65%) and US imaging every 6-12 months for those with cirrhosis but no cancer may reduce mortality of hepatocellular carcinoma by up to a third.¹⁾

• cirrhosis
  • 5 year cumulative risk of hepatocellular carcinoma in patients with cirrhosis 5-30% depending upon:
    • cause: highest risk with HCV
    • region/ethnicity: Japan 30%, USA 17%
    • stage of cirrhosis: highest risk is among those with decompensated disease
  • globally, chronic HBV infection accounts for 50% of all cases, and virtually all childhood cases
    • although HBV can cause cancer without cirrhosis, 70-80% of cancer patients due to HBV have cirrhosis
    • risk of cancer with chronic HBV increases if either:
      • stage of cirrhosis
      • long duration of HBV infection
      • male
      • elderly
      • FH hepatocellular carcinoma
      • exposure to mycotoxin aflatoxin
      • have used alcohol or tobacco
      • co-infected with HCV or hepatitis delta virus
      • high levels of HBV hepatocellular replication (ie. high levels of HBV DNA)
      • infected with HBV genotype C
  • HCV infection confers a 15-20x risk of hepatocellular carcinoma (but most of this risk is limited to those with advanced hepatic fibrosis or cirrhosis)
    • HCV epidemics: Japan 1920's; southern Europe 1940's; Nth America 1960's-70's;
    • in patients with hepatocellular carcinoma, HCV markers are found in 80-90% if Japanese, 44-66% if Italian, 30-50% if USA.
    • risk factors of hepatocellular carcinoma with HCV infection include:
      • older age at time of infection
      • males
      • coinfection with HIV or HBV
      • possibly diabetes or obesity
      • chronic heavy alcohol intake
  • prolonged heavy use of alcohol
    • daily ingestion > 40g alcohol increases risk independently by 1.5-2x, and in combination with HCV, and to a lesser extent HBV infection
• non-alcoholic fatty liver disease
  • appears to be a 1.5-2.0x risk factor for hepatocellular carcinoma but requires further study
  • 90% of obese patients have fatty liver disease, while up to 70% of type 2 diabetics have fatty liver disease

• 4 phase (unenhanced, arterial, venous and delayed) CT scan
  • should be adequate to give a diagnosis of focal hepatic mass > 2cm diameter in patients with cirrhosis
  • patients with lesions 1-2cm diameter generally require confirmation with dynamic contrast-enhanced MRI or an alpha-fetoprotein level > 400ng/ml
• atypical features or the absence of cirrhosis may require image guided biopsy for diagnosis
  • if biopsy negatiev, further studies should be done at 3-6 month intervals until it either disappears, grows larger, or displays diagnostic characteristics.