Hepatocellular Carcinoma

Detailed Overview

HCC is a leading cause of cancer-related death globally. Its pathophysiology is deeply intertwined with chronic liver injury, most notably from Hepatitis B (HBV), Hepatitis C (HCV), alcohol use disorder, and non-alcoholic steatohepatitis (NASH). The continuous cycle of hepatocellular necrosis and regeneration in a fibrotic environment leads to genomic instability and malignant transformation. A unique feature of HCC is that it can often be diagnosed via characteristic vascular patterns on dynamic imaging without the need for biopsy. Because HCC arises in diseased livers, prognosis and treatment depend simultaneously on tumor stage and the severity of underlying hepatic dysfunction.

Epidemiology & Demographics

Incidence: 6th most common cancer worldwide. Age distribution: Typically occurs in late adulthood (60-70 years) in Western countries, but much earlier (30-40 years) in endemic HBV regions (Asia/Africa). Gender ratio: Male predominant (3:1).

Etiological Mechanism

Malignant transformation of hepatocytes driven by chronic inflammation, viral DNA integration (in HBV), and continuous cellular turnover in the setting of cirrhosis.

Primary Causes

Primary: Chronic Hepatitis B (can cause HCC without cirrhosis) and Hepatitis C (requires cirrhosis)

Secondary: Alcoholic cirrhosis, Non-alcoholic fatty liver disease (NAFLD/NASH), Hemochromatosis, Aflatoxin B1 exposure

• Cirrhosis: The single greatest risk factor; present in ~80-90% of HCC cases regardless of etiology.
• Hepatitis B Virus (HBV): HBV DNA integrates into the host genome, acting as an oncogene even in the absence of cirrhosis.
• Aflatoxin B1: A mycotoxin from Aspergillus fungus found on improperly stored peanuts/grains; induces p53 mutations.

HCC development is a multistep process resulting from chronic liver injury. Continuous necrosis and regeneration lead to telomere shortening and chromosomal instability. Viral factors play a role: HBV integrates into the host genome, disrupting tumor suppressor genes and expressing oncogenic X protein. Molecularly, common mutations include TERT promoter mutations (maintaining telomerase activity), TP53 mutations (especially with Aflatoxin exposure), and activation of the Wnt/beta-catenin pathway. As hepatocytes transform into dysplastic nodules and then frank HCC, their blood supply shifts. Normal liver gets 75% of blood from the portal vein and 25% from the hepatic artery. HCC undergoes neoangiogenesis, deriving its blood supply almost exclusively from the hepatic artery. This unique arterialization is the basis for its radiologic diagnosis and therapies like transarterial chemoembolization (TACE).

Characteristic Clinical Presentation

• Right Upper Quadrant Pain: Dull ache due to tumor expansion and stretching of Glisson's capsule.
• Weight Loss and Cachexia: Unintentional, rapid weight loss and muscle wasting typical of advanced malignancy.
• Hepatic Decompensation: Worsening jaundice, new-onset ascites, or hepatic encephalopathy in a previously stable cirrhotic patient.
• Early Satiety: Feeling full quickly due to hepatomegaly pressing on the stomach.

Physical Examination Signs

• Palpable, firm, enlarged liver or frank abdominal mass
• Stigmata of chronic liver disease (spider angiomas, palmar erythema, caput medusae)
• Ascites (fluid wave, shifting dullness)
• Arterial bruit over the liver (due to increased arterial blood flow to the tumor)

• Portal Vein Thrombosis: Tumor invasion into the portal vein, worsening portal hypertension and ascites.
• Tumor Rupture: Spontaneous bleeding into the peritoneal cavity (hemoperitoneum) leading to hemorrhagic shock.
• Paraneoplastic Syndromes: Hypoglycemia (tumor consumes glucose or secretes IGF-2), Erythrocytosis (EPO secretion), Hypercalcemia.

Diagnostic Criteria & Guidelines

In an at-risk patient (cirrhosis or chronic HBV), HCC can be diagnosed non-invasively if multiphasic CT/MRI shows the classic LIRADS-5 pattern: arterial phase hyperenhancement with subsequent portal venous/delayed phase 'washout'. Biopsy is reserved for atypical lesions to avoid needle-track seeding.

Differential Diagnosis

• Metastatic liver disease (colon, breast, lung) - much more common than primary HCC
• Cholangiocarcinoma
• Hepatic Hemangioma or Adenoma (in non-cirrhotic patients)
• Focal Nodular Hyperplasia

Laboratory Tests & Biomarkers

• Alpha-Fetoprotein (AFP): Elevated (> 400 ng/mL is highly suspicious, but normal in up to 40% of small HCCs).
• Liver Function Panel: Elevated bilirubin, low albumin, prolonged PT/INR reflecting underlying cirrhosis.
• Hepatitis Serologies: HBsAg positive or HCV RNA positive indicating viral etiology.

Imaging Modalities & Findings

• Multiphasic CT/MRI:
• Hepatic Ultrasound:

• Very Early (BCLC 0)
  Single tumor < 2 cm, preserved liver function (Child-Pugh A), PS 0.
• Early (BCLC A)
  Single tumor or up to 3 nodules < 3 cm, preserved liver function.
• Intermediate (BCLC B)
  Multinodular disease, preserved liver function, no vascular invasion/extrahepatic spread.
• Terminal (BCLC D)
  End-stage liver function (Child-Pugh C) or severe cancer symptoms (PS > 2).

Second-Line & Adjunctive Therapy

For intermediate stage (BCLC B): Transarterial Chemoembolization (TACE). For advanced stage (BCLC C, vascular invasion): Systemic immunotherapy/targeted therapy with Atezolizumab + Bevacizumab, or Sorafenib/Lenvatinib.

Surgical & Procedural Management

Partial hepatectomy or orthotopic liver transplantation. Transplantation cures both the tumor and the underlying cirrhotic liver.

Recommended Lifestyle Changes

• Complete alcohol cessation
• Sodium restriction (to manage ascites)
• High-protein, frequent meals to combat cachexia and sarcopenia

Patient Counseling & Advice

Discuss the dual nature of the illness: managing both the cancer and the failing liver. Emphasize the importance of adherence to antiviral therapies for Hep B/C if applicable. If on a transplant list, discuss strict adherence to screening and lifestyle rules.

Follow-Up & Monitoring Schedule

Post-resection/ablation: Multiphasic CT or MRI of the liver + AFP every 3-6 months. Cirrhotics without HCC require US screening + AFP every 6 months lifelong.

Preventive Strategies

Universal Hepatitis B vaccination. Curative DAA therapy for Hepatitis C. Treatment of underlying causes of cirrhosis (alcohol cessation, weight loss for NASH).

Highly dependent on stage at diagnosis. Early stage treated with transplant has a >70% 5-year survival rate. Advanced stage treated systemically has a median survival of 1-2 years. Terminal stage survival is 3-4 months.