Liver

# Liver and Intrahepatic Bile Duct Cancer: The Stealth Threat

## Introduction: Dual Pathways to Malignancy
Hepatic malignancies comprise two distinct entities: **hepatocellular carcinoma (HCC)** (75-85% of cases) arising from hepatocytes, and **cholangiocarcinoma** developing in bile ducts. Global incidence has tripled since 1980, with over 900,000 new cases annually. The unique dual blood supply (hepatic artery and portal vein) facilitates early metastasis, contributing to a 5-year survival below 20% for advanced disease. Asia and Africa bear 85% of the global burden due to endemic viral hepatitis.

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## Causes and Risk Factors: Metabolic and Viral Triggers

### Primary Drivers
- **Chronic Viral Hepatitis**: HBV (50% of cases) and HCV (30%)
- **Metabolic Dysfunction**: MASLD/MASH cirrhosis (fastest growing cause)
- **Aflatoxin Exposure**: Contaminated grains in tropical regions

### Secondary Contributors
- **Alcohol-Related Cirrhosis**: Synergistic with viral hepatitis
- **Genetic Disorders**: Hemochromatosis, Wilson's disease
- **Biliary Diseases**: Primary sclerosing cholangitis (PSC)

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## Prevention Strategies: From Vaccination to Vigilance

### Tiered Prevention Framework
1. **Primary Prevention**
   - Universal HBV vaccination (83% efficacy)
   - Aflatoxin-contaminated food avoidance
   - Alcohol moderation (<1 drink/day for women, <2 for men)

2. **Secondary Prevention for High-Risk Groups**
   - Semi-annual ultrasound + AFP testing for cirrhotics
   - Antiviral therapy for HBV/HCV patients

3. **Tertiary Prevention**
   - Sorafenib/lenvatinib for advanced HCC
   - Liver transplantation criteria: Milan criteria (single tumor ≤5cm or ≤3 tumors ≤3cm)