The assay CA 72‑4 in particular serves as an aid in the therapeutic monitoring of carcinomas of the stomach and ovaries. The tumor associated glycoprotein (TAG) 72, also known as CA 72‑4 is a mucin protein of high molecular weight (approximately 200‑400 kD) and found on the surface of many cancer cells, including stomach, ovary, breast, colon and pancreatic cells. An antibody construct directed against TAG 72 has been proposed as an anti‑tumor agent against ovarian and prostate cancer.
Elevated serum levels are primarily found in gastric cancer patients, but can also be found in certain non-malignant diseases like pneumonia, pancreatitis, liver cirrhosis and ovarian cysts. The most important advantage of CA 72‑4 is its ability to discriminate between malignant and non-malignant gastric and ovarian diseases.
Gastric and Ovarian Cancer:
For gastric cancer, a diagnostic sensitivity of 33 % was reported for CA 72‑4.7 Monitoring treatment and disease course in patients with gastric and ovarian cancer is the main indication for CA 72‑4. After surgical intervention, CA 72‑4 levels return to normal and remain within the normal range in cases where tumor tissue is no longer present.
A diagnostic sensitivity of 47‑76 % has been reported in ovarian carcinoma. Especially for mucinous ovarian cancer, the diagnostic sensitivity of CA 72‑4 is greater than that of CA 125.