How is carcinoid syndrome diagnosed?
Because the symptoms of carcinoid syndrome are similar to those of other common conditions such as irritable bowel syndrome, carcinoid syndrome is often misdiagnosed.
"We frequently see patients who have been diagnosed and treated for another condition, such as irritable bowel syndrome or colitis," says Warner. He emphasizes that early diagnosis is crucial, since all treatments are more successful when the cancer is found early. "Diagnosing carcinoid syndrome early can make a big difference in the patient's outcome."
If your doctor suspects carcinoid syndrome, there are several tests that may be used to diagnose it. Once carcinoid syndrome is diagnosed, other tests can find where the tumors are located and if they've spread.
- Blood and urine tests. A test called a urine 5-HIAA is often used to diagnose carcinoid syndrome. It measures the amount of the hormone serotonin being made in the body over a period of 24 hours. Your doctor may also use blood tests to check the levels of a substance called chromogranin A, which is a marker for endocrine tumors.
- Imaging tests. Your doctor may use one or more types of imaging tests to find carcinoid tumors. An octreoscan is often especially helpful in diagnosing carcinoid tumors. For the scan, a small amount of radioactive material and a hormone-like substance that is attracted to carcinoid tumors are injected into a vein. A few hours later, a special camera can detect if the material has collected around any tumors. Other imagining tests, such as X-ray, CT scan, and MRI can help pinpoint the exact location of these tumors.
- Endoscopy. These tests use flexible tube (endoscope) that has a small camera at the end to look inside the body. Using various types of endoscopy, doctors can see almost all areas of the digestive tract, from the esophagus to the rectum.
- Biopsy. This test involves taking a small tissue sample from the tumor. A biopsy can be done during an endoscopy or may be done during a CT scan using a biopsy needle.
What are the treatments for carcinoid syndrome?
In many cases, treatment of carcinoid syndrome involves removing or shrinking the carcinoid tumor and managing the symptoms. Which treatments are used depends on the size of the tumor, the location of the tumor, and where it has spread. In general, treatments fall into one of these categories: