A 53-year-old man comes to the physician with progressively worsening anorexia and abdominal discomfort. He has lost 14 kg (31 lb) since the onset of his symptoms about 4 months ago. Physical examination demonstrates nontender hepatomegaly. Laboratory studies show an elevated serum alkaline phosphatase level and a marginally elevated alanine aminotransferase level. A CT scan of the abdomen with oral and intravenous contrast is shown below. Which of the following is the most likely diagnosis?

Question

A 53-year-old man comes to the physician with progressively worsening anorexia and abdominal discomfort.  He has lost 14 kg (31 lb) since the onset of his symptoms about 4 months ago.  Physical examination demonstrates nontender hepatomegaly.  Laboratory studies show an elevated serum alkaline phosphatase level and a marginally elevated alanine aminotransferase level.  A CT scan of the abdomen with oral and intravenous contrast is shown below.  Which of the following is the most likely diagnosis?

Quizplus · Accepted Answer

11ec160b_3956_215d_9249_7fe71a3b96f6_MD0001_00 The patient's contrast-enhanced CT scan shows multiple hypodense masses in the liver (arrows) consistent with metastatic liver disease. Metastases are the most common malignant neoplasms of the adult liver and are 20 times more common than hepatocellular carcinoma. The liver is the second most common site of metastatic spread (after the lymph nodes) because of its large size, dual blood supply, high perfusion rate, and the filtration function of Kupffer cells. Patients with liver metastases typically have multiple nodules throughout the liver that may replace more than 80% of the hepatic parenchyma, often resulting in marked hepatomegaly. The nodules frequently outgrow their vascular supply and become centrally necrotic and umbilicated. Even with significant metastatic involvement, patients may have no clinical or laboratory signs suggestive of hepatic insufficiency. However, once the majority of the liver parenchyma is destroyed or the major bile ducts become obstructed with tumor, patients tend to present with jaundice or abnormal hepatic enzymes (eg, elevated aminotransferases, alkaline phosphatase). (Choice A) Hepatic adenomas are uncommon, benign epithelial tumors of the liver that usually arise as a solitary mass in the right hepatic lobe. They are strongly associated with the use of oral contraceptives and anabolic steroids and are usually diagnosed in patients with upper abdominal pain or detected incidentally on imaging studies. They may rupture and cause intraabdominal hemorrhage. (Choice B) Hepatic angiosarcomas are associated with recent or remote exposure to vinyl chloride, arsenic, or Thorotrast. This tumor is extremely aggressive and is associated with a poor prognosis, as most patients die within a year. (Choice C) Hepatoblastoma is the most common liver neoplasm of children and is associated with familial adenomatous polyposis and Beckwith-Wiedemann syndromes. This neoplasm is usually fatal within a few years if not surgically resected. (Choice D) Hepatocellular carcinoma can present unifocally, multifocally, or as a diffusely infiltrative cancer. It is more common in older patients with a history of cirrhosis or infection with hepatitis B or C. (Choice E) Cholangiocarcinoma is a rare malignancy that arises from the intra- and extrahepatic bile ducts. Intrahepatic cholangiocarcinoma appears grossly as a treelike mass that grows along the biliary system, typically resulting in extensive intrahepatic metastasis. Risk factors include primary sclerosing cholangitis, fibropolycystic liver disease, and infection with liver flukes in endemic areas. The prognosis is very poor. Educational objective: Malignant hepatic lesions most often represent metastasis from another primary site (eg, breast, lung, colon); primary liver neoplasms (eg, hepatocellular carcinoma) are much less common.

A 53-Year-Old Man Comes to the Physician with Progressively Worsening