Pancreatic cystic lesions have become increasingly important in recent years because they are being detected more often thanks to advances in imaging techniques. According to the World Gastroenterology Organization, most pancreatic cysts are asymptomatic and are discovered incidentally on diagnostic imaging performed for unrelated symptoms. In a minority of cases, the initial presentation may be a symptomatic cyst manifesting as acute pancreatitis, bleeding, jaundice, or a palpable mass.

“Pancreatic cystic lesions are increasingly common, and most are found incidentally when an imaging test such as a CT scan or an MRI is performed. Between 25% and 30% of imaging tests detect a cystic lesion,” Eva Vaquero Raya, Department of Gastroenterology, Hospital Clínic de Barcelona, Barcelona, Spain, told Univadis Spain, part of the Medscape’s Professional network. The presence of these lesions has become a significant burden on health systems, according to a paper in the Spanish Journal of Gastroenterology, because physicians have difficulty distinguishing benign lesions from those with malignant potential.

Benign or Malignant?

Pancreatic cystic lesions can be grouped into two broad categories: benign lesions, such as serous cystadenomas and pseudocysts, and potentially malignant lesions, such as mucinous cystic neoplasms and intraductal papillary mucinous neoplasms (IPMNs).

“IPMNs is called that because its cells produce mucus because they often form papillary structures and because they arise in the epithelium of the pancreatic ducts. They are the most common type and have malignant potential, so they require surveillance. As for pancreatic mucinous cystic neoplasms, they are less common and are fairly characteristic lesions, usually located in the tail of the pancreas and primarily affecting women; they also have malignant potential, and depending on size and on analysis of the cyst fluid, surgery may or may not be recommended,” Vaquero Raya said.

When to Operate?

“All pancreatic surgeries are very complex, and we operate only when we are sure the lesion carries a high-risk and will progress to cancer. Most of these mucinous neoplasms are monitored. What determines whether to continue surveillance or to intervene? Size, growth, the presence of nodules and when the pancreatic duct diameter exceeds 10 mm, surgery is generally offered because the risk of malignancy is high,” the specialist added.

Guidelines

The guideline from the American Gastroenterological Association on the diagnosis and management of asymptomatic neoplastic pancreatic cysts recommends surveillance with MRI for cysts smaller than 3 cm that have no solid component and no dilated pancreatic duct. If the cyst’s size or characteristics do not change, surveillance should consist of an imaging exam during the 1st year and then every 2 years, for a total of 5 years. The guideline advises against continued surveillance of pancreatic cysts if no significant changes have been observed after 5 years of follow-up or if the patient is no longer a candidate for surgery.

Follow-Up and Monitoring

Once the initial diagnosis is made, the patient should be informed about the follow-up plan. “The first time, we tell the patient that we will do an MRI in 6 months and perform some lab tests. If everything is fine and the cyst measures less than 2 cm, the interval is extended to 1 year and then to 18 months. If it measures more than 2 cm, imaging is performed annually,” Vaquero Raya explained.

The psychological impact of living with a pancreatic cyst, combined with uncertainty about its malignant potential, should also be considered. “Once the patient accepts the diagnosis and follow-up, they prefer to be monitored. In fact, many patients resist when they reach 80 years old and are told that they will no longer be monitored,” the specialist concluded.

Vaquero Raya reported having no conflicts of interest.

This story was translated from Univadis Spain.