Note: All links within content go to MayoClinic.com

Pancreatic cysts are diagnosed more often now than in the past, but not because more people have them. Instead, improved imaging technology has made pancreatic cysts easier to find. In fact, many cysts in the pancreas — a large gland that produces digestive enzymes and hormones — are found during abdominal scans for other problems.

The good news is that most pancreatic cysts aren't cancerous. The bad news is that it's often difficult to be sure which cysts are benign and which are malignant. Your doctor may want to take a sample of the fluid in the cyst to help in the diagnosis. If you have a cyst that either is or can become cancerous, surgical removal is necessary.

Most pancreatic cysts aren't technically cysts at all. Called pseudocysts, these pockets of digestive fluids aren't lined with the type of cells found in true cysts. Instead, a pseudocyst's walls may include cells normally found in other abdominal organs, such as the stomach, intestines and the pancreas itself. Pseudocysts are not cancerous.

Many people who have pancreatic cysts, including pseudocysts, have no symptoms. When signs or symptoms do occur, they typically include:

• Persistent abdominal pain, which may radiate to the back
• A mass you can feel in the upper abdomen, where the pancreas is located
• Nausea and vomiting

In many cases, the cause of a particular pancreatic cyst is unknown. Some cysts are associated with rare illnesses — such as von Hippel-Lindau disease, which is a genetic disorder that can affect the brain, retina, adrenal glands, kidneys and pancreas.

Pseudocysts often follow a bout of pancreatitis, a painful condition in which the pancreas' digestive enzymes become active prematurely and digest some of the pancreas itself. Pseudocysts can also result from blunt trauma to the abdomen.

Heavy alcohol use and gallstones are risk factors for pancreatitis, and pancreatitis is a risk factor for pseudocysts — the most common type of pancreatic cyst.

Cysts can become infected, so you should see a doctor if you are feverish and have persistent abdominal pain.

A ruptured pseudocyst is a medical emergency. Fluid in the cyst contains enzymes activated for digestion. When a cyst ruptures, the released fluid can damage nearby blood vessels and cause massive bleeding. Seek emergency medical treatment if you have signs or symptoms of internal bleeding and shock:

• Fainting
• Severe abdominal pain
• Decreased consciousness
• Rapid heartbeat

Most pancreatic cysts can be detected by ultrasound, computerized tomography (CT) or magnetic resonance imaging (MRI) scans. Your doctor may also order an endoscopic ultrasound to visualize the cyst and to obtain fluid from the cyst for analysis. In this study, an endoscope is passed through your mouth and into your stomach and upper small intestine. The scope is equipped with ultrasound to image the cyst and a needle to obtain fluid from the cyst.

While the majority of pancreatic cysts are benign pseudocysts, doctors may suspect another type of cyst if it occurs with no previous history of pancreatitis or abdominal injury or if it has internal walls.

In some cases, the location of the cyst in the pancreas — along with your age and sex — can help doctors pinpoint what type of cyst you have.

• Mucinous cystadenoma. These cysts are usually located in the body or tail of the pancreas and occur most often in middle-aged women. Most of these are cancerous.
• Mucinous duct ectasia. More common in men, these cysts consist of dilated ductal segments, usually within the head of the pancreas. Also known as intraductal papillary mucinous neoplasms, these growths are often cancerous.
• Serous cystadenoma. These growths can become large enough to displace nearby organs, causing such symptoms as abdominal pain and a feeling of fullness. They occur most frequently in middle-aged women and become cancerous very rarely.
• Papillary cystic tumor. The least common of the nonpseudocysts, papillary cystic tumors — also known as papillary cystic neoplasm or solid and pseudopapillary neoplasm — occur most often in young women and are usually located in the body or tail of the pancreas. They are usually cancerous.

Islet cell tumors, also known as neuroendocrine tumors, are less common and more likely to be benign. Normally, the pancreas' islet cells produce insulin and other hormones. Islet cell tumors can also produce these hormones.

Appropriate treatment differs depending on the type of cyst and whether it causes symptoms. Sometimes, no treatment is necessary.

A benign pseudocyst — even a large one — can be left alone as long as it isn't causing significant symptoms or enlarging. A pseudocyst that is causing symptoms or growing larger may be drained with a needle or surgically removed.

Because a serous cystadenoma so rarely evolves into cancer, it also can be left alone unless it causes symptoms or enlarges. Your doctor may want to follow its size over time by checking repeat scans, especially if a precancerous cyst can't be ruled out. Most other types of lesions in the pancreas should be surgically removed, because of the risk of cancer.

The best way to avoid pseudocysts is to avoid pancreatitis, which is usually caused by gallstones or heavy use of alcohol. If your pancreatitis is due to alcohol abuse, you need to abstain from alcohol. If gallstones are triggering pancreatitis, you may need to have your gallbladder removed.