It happens more often than you might think: While testing for one problem, another unrelated condition is uncovered. Although alarming, such conditions often don’t require immediate treatment. Such is the case for symptomless pancreatic cysts found incidentally during a magnetic resonance imaging (MRI) or computed tomography (CT) scan that’s performed for another reason.
Treating asymptomatic cysts
If an imaging test incidentally detects a cyst, your doctor will carefully consider its characteristics and discuss with you how to proceed.
An updated American Gastroenterological Association (AGA) guideline, published in the April 2015 issue of Gastroenterology , suggests the cyst be managed with surveillance if it’s smaller than 3 centimeters (cm) and doesn’t appear to be high risk.
The proposed surveillance schedule entails a follow-up MRI in a year and then every two years for five years. Provided there’s no change in size or characteristics, imaging can stop after five years.
Some experts don’t agree with this less aggressive approach, however. Instead, they call for undertaking diagnostic studies if the cyst is larger than 1 cm and continuing MRIs past five years.
A case-by-case decision
The AGA guideline acknowledges that doctors should treat patients on a case-by-case basis and notes that these recommendations aren’t strong ones because of a limited amount of high-quality evidence available to support them. The decision whether to watch and wait or undergo further testing is one that you and your doctor must carefully weigh.
The AGA suggests further evaluation to obtain a fluid sample from the cyst if it has two or more high-risk features. The three factors that increase malignancy risk are a cyst that’s 3 cm or larger, the presence of a solid-appearing mass, or a main pancreatic duct that’s dilated.
The fluid sample is obtained using endoscopic ultrasonography-guided fine-needle aspiration. During this procedure, an endoscope with a tiny ultrasound probe is guided through the mouth and into the stomach and small intestine while you’re sedated.
A thin needle at the probe’s end is used to withdraw a small amount of fluid from the cyst for testing. If the results indicate a benign cyst, you’ll likely be placed on surveillance.
If the results suggest possible cancer, your doctor may refer you to a pancreatic surgeon to remove the cyst. The location of the pancreas adds to the surgery’s complexity, and the growth’s area and size dictate how much of the pancreas needs to be removed. For these reasons, finding an experienced pancreatic surgeon at a high-volume pancreatic center is essential.
Most patients who have surgery for incidentally detected cysts don’t have cancer. When that’s the case, the AGA says no continued surveillance is needed.
If the cyst is cancerous, the AGA suggests continuing MRIs every two years after surgery to watch for problems with the remaining pancreatic tissue, with discontinuation when patients are no longer surgical candidates. These recommendations are also controversial; some experts suggest continuing surveillance indefinitely in both cases.
The bottom line
The AGA suggests discussing the risks and benefits of treatment with your doctor to decide on the best course of action for you. For example, you may not feel comfortable with active surveillance of a cyst that has only one high-risk feature and instead opt to have more invasive testing for your peace of mind.
“Your doctor considers your past medical history as well as your overall health. Monitoring people who can’t undergo surgery because of age or another existing medical condition, for example, isn’t recommended because they can’t undergo the procedure should a cyst need to be removed,” says William Dale, M.D., Ph.D., associate professor of medicine and section chief of geriatrics and palliative medicine at the University of Chicago Medicine in Illinois.
“Some people may also prefer not to monitor with MRIs and instead see their doctors only if they experience symptoms later. Once again, each situation requires a careful discussion with your doctor.”