CA 19-9

CA 19-9 (carbohydrate antigen 19-9 or cancer antigen 19-9) is a serum antigen (monosialoganglioside) that has increased diagnostic use in the management of several malignancies, mainly of hepatopancreaticobiliary origin. It is non-specific, however, and can rise in both malignant and non-malignant conditions.

Elevated serum CA 19-9

Elevation of serum CA 19-9 has been associated with many conditions including the following:

• hepatopancreaticobiliary malignancies

  • cholangiocarcinoma

    • a CA 19-9 of >100 U/mL may have a sensitivity of 50% in diagnosing cholangiocarcinoma ³

    • when it is elevated with proven malignancy, larger unresectable tumors are generally thought to have higher levels of elevation 

  • pancreatic adenocarcinoma

    • with an upper limit of normal at 37 U/mL, the assays overall sensitivity is approximately 80% and its specificity is 90% for pancreatic adenocarcinoma ¹

    • when it is elevated with proven malignancy, larger unresectable tumors are generally thought to have higher levels of elevation ⁵

• other malignancies

  • colorectal carcinoma

  • gastric carcinoma ¹²

  • lung cancer ¹¹

  • hepatocellular carcinoma (HCC) ¹¹

  • ovarian carcinoma ¹¹

  • gallbladder cancer ¹⁴

• non-malignant hepatopancreaticobiliary conditions ⁴: the increase is generally small

  • acute and chronic pancreatitis

  • cholecystitis

    • xanthogranulomatous cholecystitis (levels may be very elevated) ¹³

  • cirrhosis

  • chronic and alcoholic hepatitis

  • acute hepatic necrosis

  • gallstones

  • non-malignant obstructive jaundice: usually should go down after relief of obstruction unless there is an associated malignancy ⁷

• non-hepatopancreaticobiliary conditions:

  • lung disorders (cystic fibrosis, pneumonia, tuberculosis, pleural effusion)

  • pelvic inflammatory disease

  • Hashimoto thyroiditis

  • rheumatoid arthritis

  • renal failure

  • systemic lupus erythematosus (SLE)

• others

  • heavy tea consumption ⁶

  • idiopathic ⁴

History and etymology

It was initially discovered by H Koprowski and co-workers in 1980 associated with colon and pancreatic cancer ⁹.