Your pathology report for serous cystadenoma of the pancreas

by Jason Wasserman MD PhD FRCPC
July 30, 2025

Serous cystadenoma is a non-cancerous tumor that develops in the pancreas. It is composed of small, fluid-filled spaces (cysts) lined by specialized cells that contain a sugar called glycogen. Most serous cystadenomas grow slowly and do not cause symptoms. They are often discovered by accident during imaging studies conducted for other purposes.

What causes serous cystadenoma?

The exact cause is not known, but some cases are linked to a genetic condition called von Hippel–Lindau syndrome. This inherited condition increases the risk of developing several types of tumors, including serous cystadenoma. However, most people diagnosed with a serous cystadenoma do not have this condition.

Where in the pancreas are serous cystadenomas found?

Serous cystadenomas can develop anywhere in the pancreas. However, most are found in the body or tail of the pancreas. In rare cases, more than one tumor can be found, especially in people with von Hippel–Lindau syndrome.

What are the symptoms of serous cystadenoma?

Most people with a serous cystadenoma have no symptoms. The tumor is often found by chance during an imaging test such as a CT scan or MRI. When symptoms do occur, they are usually caused by the tumor pressing on nearby organs. These symptoms can include:

  • Abdominal or back pain.

  • Nausea or vomiting.

  • Feeling full quickly or bloated.

  • Weight loss.

  • Diabetes (in rare cases).

Rarely, a tumor in the head of the pancreas may block the bile duct, leading to jaundice (yellowing of the skin and eyes).

How is this diagnosis made?

Doctors often suspect a serous cystadenoma based on imaging studies that show a cystic tumor in the pancreas. These tumors often have a characteristic appearance on CT or MRI scans. However, it can be difficult to tell serous cystadenoma apart from other types of cystic tumors before surgery. If surgery is performed, a pathologist will examine the entire tumor under the microscope to confirm the diagnosis.

A sample of fluid from the tumor may also be tested for certain proteins or genes. These tests can help rule out other types of cystic tumors, such as mucinous cystic neoplasms or intraductal papillary mucinous neoplasms.

What does serous cystadenoma look like under the microscope?

When examined under the microscope, the tumor is made up of small cysts lined by a single layer of uniform, cuboidal cells. These cells have clear or pale cytoplasm because they contain glycogen. The nuclei of the cells are small and round, and there are no signs of cancer such as mitotic figures (cells dividing) or nuclear atypia (irregularly shaped nuclei).

A central scar is often seen in the middle of the tumor, and small blood vessels (capillaries) may be present between the cysts.

Are there different types of serous cystadenoma?

Yes. Pathologists recognize several subtypes of serous cystadenoma, including:

  • Microcystic: This is the most common type. It consists of many tiny cysts and often has a central scar.

  • Macrocystic (oligocystic): This type has fewer but larger cysts. It can resemble other types of pancreatic cysts.

  • Solid serous adenoma: This rare type has no cysts and appears solid under the microscope.

  • Diffuse serous cystadenoma: In this type, the tumor replaces most or all of the pancreas and is often seen in people with von Hippel–Lindau syndrome.

  • Mixed serous-neuroendocrine neoplasm: Rarely, a serous cystadenoma can be found together with a neuroendocrine tumor in the same pancreas.

What is the prognosis for a person with a serous cystadenoma?

The prognosis is excellent. Most tumors do not grow or cause symptoms and do not need to be removed. For people with small, asymptomatic tumors, doctors may recommend regular follow-up with imaging to monitor for changes.

If surgery is needed (for example, because the tumor is large or causing symptoms), complete removal is usually curative. Recurrence is very rare. However, if the tumor has unusual features or is difficult to distinguish from cancer, follow-up may be advised.

Questions to ask your doctor

  • Was the entire tumor removed or will it need to be monitored over time?

  • If the tumor was not removed, how often should I have follow-up imaging or tests?

  • Does this tumor suggest I could have an inherited condition like von Hippel–Lindau syndrome?

  • What symptoms should I watch for that might suggest the tumor is causing a problem?

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