Tumor Markers

A 48-year-old woman from Mumbai with a 5-year history of cirrhosis (HCV-positive) undergoes routine surveillance ultrasound. A 2.5 cm nodule is detected in the right lobe of the liver. Serum alpha-fetoprotein (AFP) is 180 ng/mL (normal <20 ng/mL), and hepatitis C RNA is detectable. CT abdomen with contrast shows arterial phase enhancement of the nodule. Which of the following best describes the diagnostic significance of the elevated AFP in this clinical scenario?

A 52-year-old man from Delhi presents with a 3-month history of progressive jaundice, pale stools, and dark urine. On examination, he has hepatomegaly and a palpable epigastric mass. Abdominal ultrasound reveals a 4 cm hypoechoic lesion in the pancreatic head with dilated intrahepatic bile ducts. Serum CA 19-9 is markedly elevated at 320 U/mL (normal <37 U/mL), while CEA is normal. What is the most appropriate interpretation of the CA 19-9 result in this clinical context?

Which of the following tumor markers is characteristically elevated in both seminomatous and non-seminomatous germ cell tumors of the testis?

A 65-year-old man from Bangalore is found to have a 4 cm hepatocellular carcinoma in the setting of cirrhosis (Child-Pugh A). Serum AFP is 8500 ng/mL. He is not a candidate for surgical resection or liver transplantation. What is the drug of choice for first-line systemic therapy?

Which tumor marker is the most commonly elevated in ovarian epithelial cancers and is used for monitoring treatment response and detecting recurrence?