Review Question - QID 216245

A 51-year-old man presents to the office with a 3-month history of anorexia and weight loss. He denies a history of chest pain, abdominal pain, or cough. He has a history of hypertension, latent tuberculosis, and hepatitis C diagnosed 18 years ago. He is not currently taking any medications. He does not use tobacco or alcohol but reports intravenous drug usage for which he has previously attempted treatment. His temperature is 37.5°C (99.5°F), blood pressure is 128/70 mmHg, pulse is 81/min, and respirations are 20/min. Physical examination reveals mild hepatomegaly but his abdomen is otherwise soft, non-distended, and non-tender. A cardiopulmonary exam reveals no abnormalities. Laboratory results are as follows:

Hemoglobin: 10 g/dL
Leukocyte count: 10,300/mm^3 with normal differential
Platelets: 150,000/mm^3

Serum
Creatinine: 1.0 mg/dL
Glucose: 95 mg/dL
Lipase: 45 U/L
Alpha-fetoprotein level: 450 ng/mL (normal level 10 ng/mL - 20 ng/mL)
Total bilirubin: 1.2 mg/dL
Alkaline phosphatase: 190 U/L
Aspartate aminotransferase (AST, GOT): 32 U/L
Alanine aminotransferase (ALT, GPT): 45 U/L

A liver ultrasound is obtained which reveals a solitary lesion measuring 3x3 cm. Which of the following is the most likely diagnosis?