Most common primary malignant tumor of liver in adult is
**Core Concept**
The question is testing knowledge of primary liver tumors, specifically the most common malignant type in adults. Primary liver tumors originate from the liver itself, as opposed to metastatic tumors that spread to the liver from other sites. Hepatocellular carcinoma (HCC) is a type of primary liver cancer that arises from hepatocytes, the main cell type of the liver.
**Why the Correct Answer is Right**
Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer in adults worldwide. It typically develops in the context of chronic liver disease, such as cirrhosis due to hepatitis B or C infection, alcohol abuse, or non-alcoholic fatty liver disease (NAFLD). The pathogenesis of HCC involves genetic mutations and epigenetic alterations that promote hepatocyte proliferation and survival. The tumor cells often express markers such as alpha-fetoprotein (AFP), which can be used for diagnosis and monitoring.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not specified, so it cannot be evaluated.
**Option B:** Cholangiocarcinoma is a type of primary liver cancer that arises from the bile duct epithelium, but it is much less common than HCC.
**Option C:** Angiosarcoma is a rare type of primary liver cancer that originates from the endothelial cells lining the blood vessels of the liver. It is much less common than HCC.
**Option D:** This option is not specified, so it cannot be evaluated.
**Clinical Pearl / High-Yield Fact**
Hepatocellular carcinoma often presents with non-specific symptoms such as abdominal pain, weight loss, and fatigue. However, elevated levels of alpha-fetoprotein (AFP) can be a valuable diagnostic clue, particularly in patients with underlying chronic liver disease.
**Correct Answer: C. Angiosarcoma is a rare type of primary liver cancer that originates from the endothelial cells lining the blood vessels of the liver. It is much less common than HCC.