Tumor marker testing helps diagnose pancreatic cancer

Tumor marker testing is helpful in diagnosing pancreatic cancer. In addition to CA19-9, other commonly used markers in clinical practice include CA50, Span-1, Dupan-2, etc.

CA19-9 is a pancreatic cancer-related antigen, and its expression depends on the expression of Lewis blood group antigen. For Lewis-negative patients, CA19-9 test is also negative. The sensitivity, specificity and accuracy of CA19-9 in diagnosing pancreatic cancer are 83.1%, 73% and 75% respectively. However, the CA19-9 level in patients with small pancreatic cancer is not high, and the positive rate of adenocarcinoma less than 2 cm is only 60.7%. However, the CA19-9 level in patients with larger tumors is higher, with a positive rate of more than 80%. The cut-off value is set at 120kU/L. Those with a value higher than this are highly suspected of pancreatic cancer. After tumor resection, CA19-9 drops to normal values, and those with a serum critical value of 30kU/L have a better prognosis. If the tumor recurs, metastasizes or the condition worsens, CA19-9 will increase significantly again. Therefore, CA19-9 is an effective marker for pancreatic cancer.

CA50 is an antigen of the Lewis system and has a good correlation with CA19-9. It is not necessary to measure these two antigens at the same time. However, the combined detection of CA50 and CA242 can improve the sensitivity of pancreatic cancer diagnosis.

Span-1 adenocarcinoma patients can be as high as 1446KU/L. Its sensitivity is 81% and specificity is 68%, but it is not ideal for the diagnosis of small pancreatic cancers, with a positive rate of only 56% for tumors less than 2 cm.

The critical value of Dupan-2 is 400KU/L, and its sensitivity to pancreatic cancer is 50%-70%. Combined detection with CA19-9 can increase the positive rate to 95%. The gallbladder is affected by liver function and is closely related to GOT.