Chromogranin A test is to detect tumors in the gastrointestinal (GI) tract and sometimes the lungs. This test also detects the neuroendocrine tumors. Blood sample is required from the patient for this test.
To help diagnose and monitor carcinoid tumors and other neuroendocrine tumors when you have symptoms suggestive of a carcinoid tumor, such as flushing, diarrhea, and/or wheezing.
The level of chromogranin A in the blood is normally low. An increased CgA level in a person with symptoms may indicate the presence of a tumor, but it is not specific for the type of tumor or its location. In order to diagnose the condition, the tumor itself must be located, biopsied, and examined by a pathologist. The healthcare practitioner will frequently follow an abnormal test result with an order for an imaging scan to help locate any tumor(s) that may be present.
