Pancreatic Cysts (cont.)
Bhupinder Anand, MD
In this Article
How are pancreatic cysts diagnosed?
Since the majority of pancreatic cysts are small and produce no symptoms, they often are discovered incidentally when abdominal scans (ultrasound [US], computerized tomography or CT, magnetic resonance imaging or MRI) are performed to investigate unrelated symptoms. Unfortunately, ultrasound, CT, and MRI cannot reliably distinguish benign cysts (cysts that usually need no treatment) from precancerous and cancerous cysts (cysts that usually require surgical removal).
Endoscopic ultrasound (EUS) is becoming increasingly useful in determining whether a pancreatic cyst is likely to be benign, precancerous, or cancerous. During EUS, an endoscope with a small ultrasound transducer at its tip is inserted through the mouth, esophagus, and stomach into the duodenum. From this location which is very close to the pancreas, liver, and gallbladder, accurate and detailed images can be obtained of the liver, pancreas and the gallbladder.
During EUS, fluid from cysts and samples of tissue also can be obtained by passing special needles through the endoscope and into the cysts. The process of obtaining tissue or fluid with a thin needle is called fine needle aspiration (FNA).
The fluid obtained by FNA can be analyzed for cancerous cells (cytology), amylase content, and for tumor markers. Tumor markers, such as CEA (carcinoembryonic antigen), are proteins produced in large quantities by cancer cells. For example, pancreatic pseudocyst fluid will typically have high amylase levels but low CEA levels. A benign serous cyst adenoma will have low amylase and low CEA levels, whereas a precancerous or cancerous mucinous cyst adenoma will have low amylase levels but high CEA levels. Most recently, DNA from cells that are aspirated from the cyst has been analyzed for changes suggestive of cancer.
The risks of EUS and fine needle aspiration are small and consist of a very small incidence of bleeding and infection.
Occasionally, it is difficult even with the diagnostic tools of EUS and fine needle aspiration to determine if a pancreatic cyst is cancerous or precancerous. If the answer is not clear, sometimes repeated EUS and aspiration are done if the suspicion for cancer or precancer is high. In other cases, the cyst is reexamined by CT, MRI, or even EUS after a few months to detect changes that more strongly suggest that cancer has developed. In still others, surgery is recommended.
Medically Reviewed by a Doctor on 3/20/2013
Viewers share their comments
Pancreatic Cysts - Diagnosis Question: How were your pancreatic cysts diagnosed?
Pancreatic Cysts - Symptoms Question: What were your symptoms associated with pancreatic cysts?
Pancreatic Cysts - Types Question: Were you diagnosed with an inflammatory or non-inflammatory pancreatic cyst? Please share your experience.