A pancreatic cyst was found on MRI. Is it cancer?

In the vast majority of cases, no. Most cysts are benign or low-risk. MRI with MRCP, and sometimes endoscopic ultrasound, is needed to determine the cyst type and whether surgery is required.

How often should MRI be done if the cyst is monitored?

For branch-duct IPMN without warning signs — at 6 months, then yearly, as long as the patient would be fit for surgery. Pseudocysts and serous cystadenomas usually do not need long-term follow-up.

An intraductal papillary mucinous neoplasm — a cystic tumor growing in the pancreatic ducts. Main-duct IPMN has a high risk of cancer and is usually removed; branch-duct IPMN is most often just monitored.

Can just the cyst be removed rather than part of the pancreas?

Sometimes, yes: small cysts away from the main duct are enucleated, preserving the pancreas. But when there is a risk of cancer, a standard resection with lymph nodes is needed.

A pseudocyst after pancreatitis — does it need to be removed?

No, if it causes no complaints: many pseudocysts shrink on their own. If there is pain, compression of the stomach or infection, they are drained, most often endoscopically into the stomach.

Pancreatic cysts: surveillance or surgery

Pancreatic cysts are increasingly found by chance — on CT or MRI done for other reasons. Many of them are low-risk and will never become a problem. But some cysts — the mucinous ones — can turn into cancer over time, and these are the ones that must be recognized in time. So the key question with a pancreatic cyst is not “remove it or not” but “what kind of cyst is it”: the type determines whether surveillance is enough or surgery is needed, in which case the operation most often prevents cancer rather than treats it.

Kateryna Valikhnovska, MD, surgical oncologist, during a laparoscopic operation — The laparoscopic stage of an operation: the lights in the operating room are dimmed because the surgeon works from the camera image on the monitor.

Types of pancreatic cysts

Pseudocysts form after acute or chronic pancreatitis — collections of fluid with a fibrous wall and no tumor lining. Serous cystadenomas are benign tumors that almost never become malignant. Mucinous cystic neoplasms occur mainly in women, in the body and tail of the pancreas, and carry a risk of malignant change.

Intraductal papillary mucinous neoplasms (IPMN) grow in the pancreatic ducts. Main-duct IPMN carries a high risk of cancer; branch-duct IPMN a much lower one, and most are simply monitored. Rare solid pseudopapillary neoplasms, mainly in young women, and cystic neuroendocrine tumors also occur.

Are there symptoms

Most cysts cause no symptoms. Pseudocysts after pancreatitis may cause pain, a feeling of fullness and vomiting if they compress the stomach or bowel. Warning signs in a cyst already under surveillance — jaundice, bouts of pancreatitis, new-onset diabetes, weight loss — may indicate malignant change and call for an unscheduled work-up.

Examinations needed

MRI with MRCP — the main test: cyst size, its connection to the ducts, main duct width, and nodules in the wall.
Endoscopic ultrasound — when there are warning signs or doubts about the cyst type; cyst fluid can be sampled for cytology, CEA and amylase.
Contrast-enhanced CT — when MRI is not possible or for surgical planning.
CA 19-9 tumor marker and blood glucose.

When surgery is needed

Surgery is recommended when the risk of cancer outweighs the risk of the operation itself. For IPMN, absolute indications are tumor cells on cytology, a solid component, jaundice caused by the cyst, a mural nodule of 5 mm or more, and main duct dilation of 10 mm or more. Relative indications are cyst size of 4 cm or more, growth of 5 mm or more per year, moderate main duct dilation, a smaller mural nodule, CA 19-9 above 37 U/mL, and pancreatitis or new diabetes linked to the cyst. With relative indications, the decision depends on the patient’s age and condition.

Mucinous cystic neoplasms of 4 cm or more or with warning signs are removed; solid pseudopapillary neoplasms are always removed. Serous cystadenomas are operated on only if they cause symptoms. Pseudocysts are treated only when they cause complaints — most often by endoscopic drainage.

If surgery is not needed

Most cysts are monitored. Branch-duct IPMN without warning signs is followed with MRI and CA 19-9 — every 6 months in the first year, then yearly. Surveillance continues as long as the patient would be fit for surgery if it became necessary.

How the operation is performed

The extent depends on location: for a cyst in the head — pancreaticoduodenectomy; in the body and tail — distal pancreatectomy, sometimes preserving the spleen; carefully selected small low-risk cysts away from the main duct can be enucleated, preserving most of the pancreas. Extensive main-duct IPMN sometimes requires removal of the whole pancreas. The resection margin is checked by frozen section during surgery.

When the cyst’s location and the extent of resection allow, the operation is performed laparoscopically, through several small incisions.

Surgery for a mucinous cyst is most often cancer prevention. That is why it is done in time, but only for those who truly need it.

Kateryna Valikhnovska, MD, surgical oncologist

Recovery after surgery

Care follows the enhanced recovery after surgery (ERAS) protocol: early mobilization, early feeding, controlled pain relief. The most common complication is a pancreatic fistula, which is usually managed without reoperation. After distal pancreatectomy some patients need diabetes treatment, and after resection of the head — enzymes with meals.

Follow-up

After removal of an IPMN, the remaining pancreas continues to be monitored, because new IPMNs may appear elsewhere. After removal of a serous cystadenoma or pseudocyst, follow-up is usually not needed. The doctor sets the schedule based on the pathology.

What to bring to the consultation

MRI with MRCP or CT discs with reports — the discs themselves, ideally several scans over time;
endoscopic ultrasound and cyst fluid results, if performed;
CA 19-9, glucose and chemistry panel;
records of any previous pancreatitis;
information about pancreatic cancer in the family.

If some materials are missing, that is no reason to postpone the consultation: some examinations can be done on site.

The consultation is free of charge. How it goes and how long it takes is described on the page “Oncologist Consultation”.