hepatocellular carcinoma

hepatocellular carcinoma
Name	Hepatocellular carcinoma
Synonyms	Hepatoma
Caption	Axial CT scan of the liver showing a typical enhancing mass (arrow).
Field	Oncology, Hepatology, Gastroenterology
Symptoms	Abdominal pain, weight loss, jaundice
Complications	Liver failure, Metastasis
Causes	Cirrhosis, Hepatitis B virus, Hepatitis C virus
Risks	Aflatoxin, Alcoholism, Non-alcoholic fatty liver disease
Diagnosis	Alpha-fetoprotein, Medical imaging, Liver biopsy
Differential	Hemangioma, Focal nodular hyperplasia, Cholangiocarcinoma
Prevention	Hepatitis B vaccination, antiviral therapy
Treatment	Surgical resection, Liver transplantation, Ablation therapy
Medication	Sorafenib, Lenvatinib, Atezolizumab
Prognosis	Variable, depends on stage
Frequency	~1 million new cases annually

Hepatocellular carcinoma is the most common primary malignancy of the liver. It arises from hepatocytes and is a major global health problem, particularly in regions with high prevalence of chronic liver disease. The development is strongly linked to underlying cirrhosis and chronic infection with Hepatitis B virus or Hepatitis C virus. Clinical presentation is often insidious, with advanced disease manifesting as abdominal pain, weight loss, and jaundice.

Epidemiology

The incidence exhibits significant geographical variation, with the highest rates observed in East Asia and Sub-Saharan Africa, largely driven by endemic Hepatitis B virus infection. In contrast, rates in North America and Western Europe are lower but have been rising, attributed to the increasing prevalence of Non-alcoholic fatty liver disease. According to the World Health Organization, it represents a leading cause of cancer-related mortality worldwide. The Global Burden of Disease Study consistently highlights its substantial impact on public health systems, particularly in developing nations.

Risk factors

The predominant risk factor is established cirrhosis from any cause, including chronic viral hepatitis and Alcoholism. Infection with Hepatitis B virus is a major independent risk factor, even in the absence of cirrhosis, due to viral integration into the host genome. Other significant factors include chronic Hepatitis C virus infection, exposure to dietary Aflatoxin (a mycotoxin produced by Aspergillus flavus), and metabolic conditions like Non-alcoholic fatty liver disease and Diabetes mellitus. Less common associations include hereditary conditions such as Hemochromatosis and Alpha-1 antitrypsin deficiency.

Pathophysiology

Carcinogenesis typically occurs in a background of chronic hepatic injury, inflammation, and regeneration, which leads to genetic and epigenetic alterations in hepatocytes. Key molecular pathways involved include the Wnt signaling pathway, TP53 tumor suppressor gene mutations, and activation of Telomerase reverse transcriptase. In cases related to Hepatitis B virus, viral DNA integration can disrupt critical host genes. The progression from dysplastic nodules to early then advanced carcinoma is a well-characterized sequence often studied at institutions like the National Cancer Institute.

Diagnosis

Surveillance in high-risk patients involves periodic ultrasound and measurement of serum Alpha-fetoprotein levels. Diagnostic confirmation for characteristic lesions often utilizes multiphase CT scan or MRI, with typical features being arterial enhancement and venous washout. The LI-RADS (Liver Imaging Reporting and Data System) classification, developed by the American College of Radiology, standardizes imaging interpretation. A definitive diagnosis sometimes requires Liver biopsy, though this is avoided when imaging is conclusive due to risks like tumor seeding. Differential diagnoses include benign entities like Hemangioma and other malignancies such as Cholangiocarcinoma.

Treatment

Treatment strategy is dictated by tumor stage, liver function, and patient performance status. Curative options for early-stage disease include Surgical resection or Liver transplantation, with the latter guided by criteria such as the Milan Criteria. For patients not eligible for surgery, locoregional therapies like Radiofrequency ablation or Transarterial chemoembolization are employed. For advanced disease, systemic therapy with multikinase inhibitors like Sorafenib and Lenvatinib, or immunotherapy combinations such as Atezolizumab with Bevacizumab, are standard. Research from centers like the Memorial Sloan Kettering Cancer Center continues to evaluate novel agents and combination strategies.

Prognosis

Overall prognosis remains poor, largely because diagnosis often occurs at an advanced stage. Survival is highly dependent on the stage at presentation and the success of therapeutic intervention. The Barcelona Clinic Liver Cancer staging system is widely used to stratify prognosis and guide management. Long-term survival is excellent for patients who undergo successful Liver transplantation for early tumors within the Milan Criteria. Outcomes for advanced disease, despite improvements with new systemic therapies, are generally measured in months, highlighting the critical need for early detection and prevention strategies championed by organizations like the Centers for Disease Control and Prevention.

Category:Liver cancer