What is Pancreatic Cysts?
The pancreas is a vital part of the digestive system. It makes enzymes to help break down food and also releases essential hormones into our blood, aiding metabolism. Sometimes, people might have ‘pancreatic cysts’, which are fluid-filled sacs, found in the pancreas. Often these cysts are spotted in patients who are having CT or MRI scans for different health reasons. As our population gets older and the use of these scans increases, we’re finding more people with pancreatic cysts. Indeed, between 2% and 20% of people going through a CT or MRI scan are found to have them, though the percentage may be slightly lower in individuals who’ve never had pancreatitis, a condition in which the pancreas gets inflamed.
It’s also worth noting that in patients who are at high risk due to a family history of pancreatic cancer, up to one-third might have pancreatic cysts. There are two main types of pancreatic cysts; neoplastic and nonneoplastic. Neoplastic cysts – which means they are formed by abnormal tissue growth – include certain types like IPMN, mucinous cystic neoplasm, solid pseudopapillary neoplasm, and cystic pancreatic neuroendocrine tumors. IPMN can be further divided into main duct IPMN, branch duct IPMN, and mixed IPMN. Non-neoplastic cysts – ones not made from abnormal tissue growth – include types like serous cystic adenoma, simple cysts, lymphoepithelial cysts, and mucinous nonneoplastic cysts. It’s really crucial to get the right diagnosis because the next steps – how doctors choose to manage the cyst – depend on whether the cyst is neoplastic or nonneoplastic.
Importantly, not all pancreatic cysts require surgery. In fact, surgical removal can be complicated and come with associated risks. Sometimes, only monitoring the cyst is the best option depending on the type of cyst, how quickly it’s growing, and what symptoms the patient is experiencing. Especially since there’s growing concern about pancreatic cysts and their potential to develop into cancer, there’s been progress in the way doctors can keep an eye on these cysts and confirm their diagnosis. For instance, endoscopic ultrasound – a procedure that allows doctors to examine the digestive tract and nearby organs – has made a big difference in early detection and guiding the treatment for pancreatic cysts.
What Causes Pancreatic Cysts?
The cause of pancreatic cysts, which are fluid-filled pockets in the pancreas, can be quite different based on whether they are non-cancerous (non-neoplastic) or cancerous (neoplastic). Interestingly, these cysts are often discovered by chance during other medical examinations.
Risk factors that can increase the chances of developing pancreatic cysts include a history of pancreatic cancer and/or pancreatitis, a type of inflammation of the pancreas.
Cancerous pancreatic cysts can include Intraductal Papillary Mucinous Neoplasms (IPMN), which come in three types: main duct IPMN, branch duct IPMN, and mixed IPMN, mucinous cystic neoplasm, solid pseudopapillary neoplasm, and cystic pancreatic neuroendocrine tumors. These cyst types are all related to different types of cells in the pancreas becoming cancerous.
On the other hand, non-cancerous pancreatic cysts may include serous cystic adenoma, simple cysts, lymphoepithelial cysts, and mucinous nonneoplastic cysts. These types of cysts can form due to various causes but are generally not cancerous.
Risk Factors and Frequency for Pancreatic Cysts
It’s not easy to determine how often pancreatic cysts happen, but certain types of cysts appear more frequently in surgical cases. Here’s a breakdown of how often different types of pancreatic cysts were found in a series of surgeries:
- 26% were branch duct IPMN
- 25% were main duct IPMN
- 13% to 23% were serous cystadenoma
- 11% to 18% were mucinous cystic neoplasm
- 4% to 7% were cystic pancreatic neuroendocrine tumors
- 2% were solid pseudopapillary neoplasms
Signs and Symptoms of Pancreatic Cysts
If someone has a history of pancreatitis, a family history of pancreatic cancer, or multiple endocrine neoplasia type 1, they may be at risk for certain health issues. These people often show no symptoms, but they might experience abdominal pain, back pain, weight loss, jaundice (yellowish skin), steatorrhea (fat in the stools), or they might be able to feel a lump in the abdomen area.
Because these signs and symptoms are pretty general and could point to many different conditions, it’s important for doctors to take a detailed account of any other potential causes. So, the person’s history of alcohol and tobacco use; use of non-steroidal anti-inflammatory drugs (NSAIDs); history of liver, pancreatic, peptic (stomach), or biliary (bile duct) disease; or history of fevers or chills will also need to be considered.
- History of pancreatitis
- Family history of pancreatic cancer
- Presence of multiple endocrine neoplasia type 1
- Symptoms like abdominal pain, back pain, weight loss
- Jaundice (yellowing of skin)
- Steatorrhea (fat in stools)
- Palpable mass in the abdomen
- History of alcohol and tobacco use
- NSAIDs use
- History of liver, pancreatic, stomach, or bile duct disease
- History of fevers or chills
Testing for Pancreatic Cysts
Pancreatic cysts, or small sacs of fluid on your pancreas, are often discovered by chance during CT or MRI scans. What happens next depends on what these images show and if you have any symptoms. As our understanding of pancreatic cysts develops, the guidelines for their evaluation and treatment continue to change.
The American Gastroenterology Association gives doctors guidelines to follow when asymptomatic (not showing symptoms) pancreatic cysts are found incidentally (by accident). These guidelines help doctors classify cysts as either high or low risk for developing into cancer, based on what the images show and patient symptoms. Features suggesting a high risk include symptoms, enlarged lymph nodes, a wide main pancreatic duct (more than 5 mm wide), and certain characteristics of the cyst itself. These characteristics include a sudden change in the main pancreatic duct, a small mass in the cyst wall, a solid part that enhances imaging, thickened walls, and a big cyst (more than 3 cm big).
Based on these risk factors, the guidelines recommend one of three approaches. These could be either watching the cyst over time with no action, pulling fluid from the cyst for examination through endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), or surgery.
If you have a symptomatic pancreatic cyst (a cyst causing symptoms), surgical removal is the preferred treatment. It can ease the symptoms and is recommended because pain tends to be linked with a higher chance of it being or becoming cancerous.
If a patient has a high-risk cyst (as defined above), or if the main pancreatic duct is wide, or if the doctors suspect a mucinous cyst (a particular type of cyst) or another specific type of cyst (called branch duct IPMN) being more than 3 cm big, the guidelines recommend surgical removal.
In the case of low-risk cysts, like a microcystic serous cystadenoma (a particular cyst type), they usually can be watched over time as they have a very small chance of becoming cancerous. However, if you have a certain type of cyst (macrocystic serous cystadenomas), it might be difficult to distinguish from mucinous lesions on an imaging test, and it needs to be evaluated by EUS-FNA to test the fluid for certain levels of a substance called carcinoembryonic antigen (CEA).
EUS-FNA is a procedure that can give more details about the lesion and help to avoid the wrong diagnosis. It can analyze the fluid in cysts for mucus, CEA, and cell types. High levels of CEA suggest mucinous lesions. Further, examining the cells in the fluid can help to differentiate between harmful and non-harmful lesions.
Treatment Options for Pancreatic Cysts
According to the American Gastroenterological Association, the management of asymptomatic incidental cysts – cysts that are discovered during tests for unrelated conditions and don’t show any symptoms – varies based on the initial imaging and symptom findings. They suggest dividing the management into three categories: monitoring, a procedure known as an EUS-FNA, or surgery.
Monitoring is suggested for smaller cysts that are less than 3 cm and don’t have a solid component. Additionally, they shouldn’t show a dilation or enlargement of the main pancreatic duct. In contrast, EUS-FNA, which is a minimally invasive procedure to collect cells for further analysis, is recommended if the cyst is larger than 3 cm, has a solid component, or the main pancreatic duct is dilated. At least two of these criteria must be met for the recommendation of EUS-FNA. Lastly, if there is both a solid component and main pancreatic duct dilation or if EUS-FNA indicates suspicious findings, surgery is proposed.
If the decision is to monitor, an MRI scan should happen a year later and then every two years after that. If the cyst has not changed five years into monitoring, it can be stopped. However, if a change in the cyst is noticed, EUS-FNA should be performed. On the other hand, If surgery was the initial option and the examination of the tissue removed shows high-grade dysplasia or cancer, an MRI should be done every two years thereafter.
Specific types of cysts such as main duct IPMN, mixed IPMN, and mucinous cystic neoplasms should always be removed through surgery. Whether to remove a branch duct IPMN depends on if the patient displays symptoms, the presence of an enhancing solid cyst component, main pancreatic duct diameter being greater than 5mm, traces of suspicious or positive findings of cancer in the cyst fluid, or an alteration in the main pancreatic duct with loss of mass in the distal pancreas.
What else can Pancreatic Cysts be?
When a doctor discovers a pancreatic cyst, they might find that the symptoms can suggest a wide variety of conditions. Other conditions they might need to rule out include pancreatitis, liver ailments, disorders of the bile-producing system, and stomach diseases. By conducting a thorough medical history review, physical examination, lab tests, and medical imaging, the doctor can effectively identify the true condition. Oftentimes, pancreatic cysts are spotted incidentally during imaging processes for other reasons, so some other potential conditions can be simultaneously ruled out. It’s always important to have regular checkups to ensure our health is in optimal condition.
What to expect with Pancreatic Cysts
The type of pancreatic cyst someone has can affect their risk of it becoming cancerous. Certain types that aren’t invasive (which means they don’t spread) usually have a very good outlook.
Here are some statistics for survival over five years, meaning the number of people who are still alive five years after their diagnosis:
- For those with noninvasive main duct IPMN (a type of pancreatic cyst) which has been surgically removed, nearly 100% are still alive after five years. But, if the cyst turns out to be cancerous, about 60% of people are still alive after five years.
- For branch duct IPMN that is cancerous and has been surgically removed, the survival rate is around 70%.
- For noninvasive mucinous cystic neoplasm, another type of pancreatic cyst, about 96% of people survive over five years. If it’s invasive and has been surgically removed, the survival rate is approximately 75%.
- For cystic pancreatic neuroendocrine tumor, the survival rate is approximately 77%.
- We don’t have much information about the survival rate for solid pseudopapillary neoplasm because it’s a rare condition.
Preventing Pancreatic Cysts
Take note of the symptoms mentioned earlier. If you start to notice these, it’s important that you get medical help right away.
