Q1: “I recently underwent a CT scan of the abdomen for evaluation of kidney stones. My doctor told me that there is a cyst located in my pancreas. He referred me to a gastroenterologist, and it was advised that I should undergo an endoscopy to further evaluate this. Should I be worried about the cyst?”
Christopher DiMaio, MD
Mount Sinai School of Medicine
Pancreatic cysts are being diagnosed more and more frequently today as the use of high-quality CT scans (“CAT scans”) and MRI tests are increasingly being performed. Most often, a cyst in the pancreas is found incidentally or by accident, because the scan was being performed for another unrelated reason (like to evaluate kidney stones in the patient submitting Question 1).
A cyst refers to a fluid-filled “bubble”. In the pancreas, cysts can form for a variety of reasons. For example, in patients who have had a history of pancreatic inflammation, called pancreatitis, fluid that has leaked out of the pancreas can form an organized collection called a pseudocyst. Other types of cysts are considered neoplastic, which means that they form as a result of abnormal growth of cells, such as a tumor. Some pancreatic cysts are considered benign neoplasms (or tumors), meaning that while they may continue to grow in size, there is no chance they will turn into a cancerous tumor or have the potential to spread to other organs. On the other hand, some pancreatic cysts are considered pre-cancerous (or pre-malignant), meaning that they have the potential to turn into a cancerous cyst and thus invade adjacent organs or spread to other parts of the body.
An easier way to divide up these different classes of cysts is to categorize them as either “non-mucinous cysts” or “mucinous cysts”. This refers to the type of fluid these cysts contain. “Non-mucinous cysts” refer to the fact that these cysts contain a very thin, watery type of liquid inside. Non-mucinous cysts are all benign, and have no chance of turning cancerous. Mucinous cysts, on the other hand, are filled with a thick, sticky fluid which is produced by the cells lining the cyst cavity. Mucinous cysts have the potential to turn cancerous. However, just because a mucinous cyst is discovered does not mean that cancer is present.
As gastroenterologists, when we evaluate patients with a pancreatic cyst, we are faced with two important questions to answer: 1) Is the cystic lesion a “non-mucinous” kind, or is it “mucinous”?; 2) If it is the mucinous kind, is there cancer present in it? In order to answer these questions, a number of tests may need to be performed in order to determine the type of cyst you have and if there are any high-risk features worrisome for cancer. These tests may include blood work, CT scans, a special type of MRI scan called an MRCP, or endoscopic tests designed to study the pancreas such as endoscopic ultrasound or ERCP (endoscopic retrograde cholangiopancreatography).
Unfortunately, there is not one best test that can be used to confirm the diagnosis. Most physicians rely on a combination of imaging tests and endoscopy tests to help make a diagnosis. In addition, certain aspects of your personal medical history as well as family history can help your physician in the evaluation.
Not all pancreatic cysts are worrisome. However, due to the fact that some cysts may in fact be pre-cancerous, a complete evaluation by a gastroenterologist and/or pancreatic disease specialist is warranted when a person is found to have a pancreatic cyst.
Q2: I have been diagnosed with a type of pancreas cyst called an IPMN. My doctor said that I may need to have surgery? What determines whether or not I should have surgery? Are there other treatment options available?
IPMN stands for intraductal papillary mucinous neoplasm. It is a type of pancreatic cyst that forms from abnormal changes in the cells lining the pancreatic ducts (the tubes that run inside the pancreas and carry digestive juices to the small intestine). There are three different types of IPMN:
- Main duct IPMN – these involve the main pancreatic duct that runs through the pancreas
- Branch duct IPMN – these involve the small side ducts that branch off of the main pancreas duct
- Mixed-type IPMN – these involve BOTH the main pancreatic duct and the small side ducts
IPMN are a type of “mucinous cyst” (discussed in the answer to Question 1). All IPMN are considered pre-cancerous, much like a colon polyp is considered pre-cancerous. However, some IPMN are considered to be at higher risk than others for having or developing cancer. Main duct IPMN are considered high-risk lesions for pancreas cancer. On the other hand, small branch duct IPMN (those smaller than 3 centimeters in size) are considered low-risk for developing pancreatic cancer.
Given that all IPMN are pre-cancerous lesions, surgical resection may be recommended. The decision as to whether or not surgery should be performed is based on a number of factors, including the health of the patient, the size of the cyst, and the presence or absence of certain high-risk cyst characteristics.
In some patients, surgery may not be offered or recommended, usually because the cystic lesion is deemed low-risk, or because the risk of the surgery may outweigh the benefit. In these cases, most physicians will recommend that the pancreatic cyst be surveyed with repeat scans (either CT scan or MRI/MRCP). In my practice, I typically repeat a scan in 3-6 months depending on the cyst type and features. If there are no changes, I will double the interval for the next scan (to 6-12 months). The purpose of this is to watch the cyst over time, to see if it grows or develops high-risk changes. If the cyst changes unfavorably, surgery may then be required.
The type of surgery one would need depends on the cyst location and features. In some cases, only a small amount of the pancreas needs to be removed. In other cases, a large portion or even the entire gland may need to be removed. In some centers, certain cysts may be able to be enucleated with no need to remove large parts of the pancreatic gland.
One other treatment option available is called EUS-guided cyst ablation. This is a minimally-invasive endoscopic procedure whereby a gastroenterologist performs a type of endoscopic procedure called endoscopic ultrasound (EUS). With EUS, highly-detailed images of the pancreas can be obtained. At the same time, a needle can be inserted into the cyst and a combination of agents can then be injected into the cyst cavity. The idea is that these agents can destroy the cells lining the cyst cavity and possibly prevent the cyst from growing or turning cancerous. This is considered an experimental treatment and is not considered part of the standard of care. However, some medical centers are currently performing this treatment as part of research protocols.
Q3: Are cyst in the pancreas related to the liver cysts or kidney cysts?
In general, pancreatic cysts are not related to cysts that develop in the liver or kidneys. It should be noted that just because someone is found to have a benign liver or kidney cyst, it does not mean that there pancreas cyst is also likely to be benign, or vice versa.
Q4: I had a bout with acute necrotizing pancreatitis in which the body of my pancreas had to be removed surgically. The tail has been causing pancreatic cysts since it is no longer connected and I have had two surgeries and a couple of endoscopes to have them drained. In a situation like this, do you know of any techniques that can help prevent these cysts from re-occurring without having to surgically remove the tail?
Pancreatic pseudocysts form after the pancreas has suffered a bout of severe inflammation and/or trauma, with resulting leakage of pancreatic fluid around the pancreatic gland. Over time, the leaked fluid coalesces and organizes into a collection of fluid. This fluid collection is surrounded and contained by a wall, which is made up of inflammatory cells and fibrous tissue.
In approximately 50% of cases, a pancreatic pseudocyst will resolve on its own, with no need for endoscopic or surgical intervention. In the other half of patients, these cysts will cause symptoms of abdominal pain/nausea/vomiting, contribute to recurrent bouts of pancreatitis, or become infected, and thus require some type of intervention to treat them.
Traditional approaches to pseudocyst management have included surgical removal or drainage. Over the past two decades however, surgery has largely been able to be avoided by the use of interventional endoscopic techniques. This includes ERCP with pancreatic stent placement, EUS-guided cyst-gastrostomy, and endoscopic necrosectomy techniques. In many cases, a combination of these endoscopic approaches is required, or the need for multiple, repeat interventions may be needed. In some patients, a combination of both endoscopy and surgery is needed.
Approximately 10-15% of patients with pancreatic pseudocysts will have a re-occurrence. In the majority of these cases, this is due to a persistent damage in the pancreatic duct and/or an unrecognized blockage in the pancreatic duct. One or both of these conditions can contribute to persistent leakage of pancreatic juice and enzymes and the reformation or persistence of a pseudocyst.
Successful treatment typically requires a multi-disciplinary approach, preferably at a high-volume tertiary referral center where expert gastroenterologists/endoscopists/pancreatologists and surgeons are available.
This project is intended to provide information and does not constitute medical advice and it should not be relied upon as such. The National Pancreas Foundation does not recommend any particular treatment and in all cases recommends that you consult your physician. The NPF and its physician consultants disclaim all medical responsibility for any content supplied thereof to patients. While the NPF and its physician consultants will not use your name when posting the questions and answers we cannot absolutely guarantee your privacy.