What is a cyst?
A cyst is an enclosed sac of fluid. They can be a true cyst which has a lining or a ‘pseudo cyst’ which doesn’t have a true lining. The composition of the fluid may be different depending on why the cyst is present
What is a pancreatic cyst?
A pancreatic cyst is a cyst that may be inside the pancreas or adjacent to the pancreas but arising from the pancreas. Cysts can be seen in a healthy pancreas gland or can arise when the pancreas gland has been damaged by inflammation or alcohol.
Are pancreatic cysts dangerous?
Most pancreatic cysts are not dangerous. Whether the cysts can cause problems depends on what type of cyst is found in the pancreas. Certain types of cysts can cause symptoms and symptoms are more often present in larger cysts. Some cysts have the potential to either become cancerous or are cancerous at the time they are found. Symptomatic cysts, cancerous or pre-cancerous cysts may need to be removed surgically.
What are the symptoms of a pancreatic cyst?
Pancreatic cysts often cause no symptoms at all. When symptoms arise, they may be due to compression of the ducts in the pancreas. The most common symptom is pain and patients can experience episodes of pancreatitis, which may result in admission to hospital. More rarely pancreatic cysts can cause compression of the bile ducts resulting in jaundice or infection (cholangitis). Nutritional deficiencies such due to lack of digestive enzymes (particularly fat absorption is also rare as is diabetes.
What are the types of pancreatic cyst?
Simple cysts – these are often small simple cysts which are often called a retention cyst. They rarely cause symptoms and have no cancerous potential.
Pseudocysts – These are not true cysts as they lack a defined wall. They occur after damage to the pancreas, usually because of severe pancreatitis (inflammation of the pancreas gland). Pancreatitis can be caused by several causes such as alcohol, gallstones, certain medications and some viruses.
The pseudocysts contain fluid which is rich in digestive enzymes which have escaped from the pancreas. This fluid can erode into adjacent tissues and can become infected. They can cause pain and may also press onto adjacent organs, such as the stomach.
Serous cystic neoplasms (Serous cystadenomas)- These cysts, often referred to as SCN, are a fluid filled and most commonly occurs in women. There are almost always non cancerous and rarely need surgical removal. Long term observation or monitors is not required as they provide little risk. If these lesions are large and causing symptoms they can usually be removed by a keyhole approach.
Mucinous cystic neoplasms (Mucinous Cystadenoma)- Mucinous cysts of the pancreas (MCN) often grow to be quite large and in comparison to serous cysts and have thick walls often with internal divisions. The fluid inside the cysts is often thick and stringy. They don’t communicate with the pancreatic ducts like IPMN (see below). They almost always occur in the left side of the pancreas and are most commonly seen in women over the age of 40. MCNs carry a risk of cancerous change which is more often seen in larger cysts. For this reason and the prevalence of symptoms mucinous cystic neoplasms often require surgical excision.
Intraductal papillary mucinous neoplasm (IMPN) – These cysts often referred to more simply by their abbreviation IPMN, are mucin containing cysts that communicate with either the main or lesser (side-branch) pancreatic ducts. The risk of them becoming sinister is based on several factors including, the size of the duct, the size of the cyst and features of the cyst seen on imaging. Click her for more information.
What are the tests for a pancreatic cyst?
A CT scan or ultrasound is usually how a pancreatic cyst is detected. A specialist pancreatic protocol CT scan can quite accurately define a cyst from its surrounding structures and in most cases can tell the what type of cyst is present. An MRI scan may be required to define the type of cyst with a high degree of certainty. Endoscopic ultrasound is also a highly accurate way of assessing cysts of the pancreas, it is especially useful when biopsies of tissue or cyst aspiration is required and has the benefit that a tissue diagnosis may be achieved. It is also useful in people who cannot undergo MRI but does require an anaesthetic.
When does a pancreatic cyst need treatment?
In general, pancreatic cysts need treatment if they are causing symptoms, such as pain or pancreatitis or if there is a chance that they are or will become malignant (cancerous). If you have a pancreatic cyst it is the job of your doctor (usually one of the surgical doctors) to determine whether this is the case. This often requires high definition medical imaging interpreted by one of our specialist radiologists. An endoscopic ultrasound with or without a biopsy may be required, which is performed by an interventional gastroenterologist. The results of the tests performed, are presented by your primary physician to our multidisciplinary team. At this meeting all clinical history, imaging and biopsy results are reviewed by our team of surgeons, radiologists, gastroenterologists and oncologists. The team will then make a group recommendation which you will be able to discuss with your primary physician.
There are three recommendations that may arise from an asymptomatic cyst
- The cyst may be low risk, such as a serous cystic neoplasm, and not need further monitoring or treatment
- The cyst may be indeterminant risk and require careful observation with repeated testing at short intervals, such as a side branch IPMN
- The cyst may be high risk or could already be malignant in which case surgery to remove the cyst and adjacent pancreas may be required.
People with symptomatic cysts may be offered surgery depending on their fitness for surgery and severity of symptoms