In medicine, HCC stands for Hepatocellular Carcinoma. This is the most prevalent form of primary liver cancer, meaning it originates directly in the liver rather than spreading from another part of the body. Its global impact and challenges in early detection and management make it a significant medical concern.
Understanding Hepatocellular Carcinoma
Hepatocellular Carcinoma (HCC) is a type of cancer that develops in the hepatocytes, which are the main cells of the liver responsible for most of its functions. As the most common form of primary liver cancer, HCC accounts for over 90% of primary liver tumors. This distinction from metastatic liver cancer, where cancer cells travel to the liver from a tumor elsewhere in the body, is important for understanding its unique characteristics.
HCC is recognized for its aggressive nature, particularly if not identified in its early stages. It is the fifth most common cancer globally and the second leading cause of cancer death in men after lung cancer. In 2018, approximately 841,000 new cases of HCC were diagnosed worldwide, with around 780,000 deaths attributed to the disease. Over 80% of new cases occur in developing countries, especially in regions with high burdens of hepatitis B virus infection, such as Sub-Saharan Africa, Southeast Asia, and China.
Factors Contributing to Its Development
The development of Hepatocellular Carcinoma is closely linked to underlying liver damage and chronic inflammation, often stemming from specific risk factors. Chronic viral hepatitis, particularly infections with Hepatitis B virus (HBV) and Hepatitis C virus (HCV), are leading causes globally. HBV can directly induce HCC even in non-cirrhotic livers, while HCV typically leads to HCC through the progression to cirrhosis.
Cirrhosis, a condition characterized by severe scarring of the liver, is a significant precursor for HCC, with the cancer occurring in 80-90% of patients with cirrhosis. Various factors can cause cirrhosis, including chronic alcohol abuse, which leads to alcoholic liver disease. Another increasingly common cause is Non-Alcoholic Fatty Liver Disease (NAFLD), which can progress to Non-Alcoholic Steatohepatitis (NASH), a more severe form of fatty liver disease that involves inflammation and liver cell damage. The rising rates of obesity and diabetes contribute to the increase in NAFLD/NASH-related HCC. Less common factors, like hemochromatosis (a disorder causing iron overload) and exposure to aflatoxins (toxins produced by certain molds found on crops), also contribute to liver damage that can lead to HCC. These conditions collectively create an environment of ongoing liver cell injury and repair, increasing the likelihood of cancerous transformation over time.
How HCC is Identified
Identifying Hepatocellular Carcinoma often involves a combination of surveillance in high-risk individuals and diagnostic procedures. For those with chronic liver disease, especially cirrhosis, regular surveillance is performed, typically every six months. This involves imaging tests like ultrasound, which can detect suspicious lesions in the liver. If an ultrasound reveals abnormalities, further imaging with computed tomography (CT) scans or magnetic resonance imaging (MRI) is often used to characterize the findings in more detail.
Blood tests also play a role in identification, with alpha-fetoprotein (AFP) being a commonly used tumor marker. While elevated AFP levels can suggest the presence of HCC, a steadily rising AFP level is more indicative. However, AFP levels alone are not definitive for diagnosis. A definitive diagnosis frequently requires characteristic imaging findings on CT or MRI, which can often negate the need for a biopsy in certain cases. When imaging is not conclusive, a liver biopsy, where a tissue sample is taken and examined under a microscope, may be performed to confirm the diagnosis. Early detection through these methods is important for improving treatment outcomes.
Managing and Treating HCC
Managing and treating Hepatocellular Carcinoma involves a range of approaches, tailored to the individual patient based on the cancer’s stage, the overall function of their liver, and their general health status. For early-stage HCC, curative treatments are often considered. Liver resection, which involves surgically removing the cancerous part of the liver, is an option when the tumor is small and liver function is preserved. Liver transplantation can be a curative option for select patients, especially those with cirrhosis and small, confined tumors, as it replaces the diseased liver entirely.
Other localized treatments focus on destroying the tumor directly within the liver:
Radiofrequency ablation (RFA) uses heat generated by radio waves to destroy cancer cells.
Transarterial chemoembolization (TACE) involves delivering chemotherapy drugs directly to the tumor through the hepatic artery, followed by blocking the blood supply to the tumor.
Stereotactic body radiation therapy (SBRT) delivers high doses of radiation precisely to the tumor while sparing surrounding healthy tissue.
For more advanced cases or when localized treatments are not feasible, systemic therapies are employed. Targeted therapy drugs work by interfering with specific molecules involved in cancer growth and progression. Immunotherapy, another systemic approach, helps the body’s immune system recognize and destroy cancer cells. Supportive care is also a component of managing HCC, focusing on alleviating symptoms and improving the patient’s quality of life throughout their treatment journey.