The Cancer Pancreatic (CA19-9) blood test is a diagnostic tool used to detect the presence of pancreatic cancer. This test measures the levels of a protein called CA19-9 in the blood, which is produced by cancerous cells in the pancreas. Elevated levels of CA19-9 can indicate the presence of pancreatic cancer, but may also be present in other conditions such as liver disease or gallstones. This test is often used in combination with other diagnostic tests to confirm a diagnosis of pancreatic cancer. It is important to note that a normal result does not necessarily rule out the possibility of pancreatic cancer.