Cystic lesions of the pancreas (differential)

The differential for cystic lesions of the pancreas includes:

• unilocular

  • pancreatic pseudocyst

  • intraductal papillary mucinous neoplasm (IPMN)

  • serous cystadenoma uncommonly uni/macrolocular

  • simple pancreatic cyst

  • cystic neuroendocrine tumor of the pancreas

• diffuse pancreatic cysts

  • pancreatic cysts occur in association with 

    • von Hippel Lindau syndrome

    • autosomal dominant polycystic kidney disease (ADPKD)

    • cystic fibrosis

• macrocystic: multilocular

  • mucinous cystic neoplasm of the pancreas: usually body and tail

  • intraductal papillary mucinous neoplasm (IPMN)

  • serous cystadenoma uncommonly uni/macrolocular

  • acinar cell cystadenocarcinoma

  • hydatid cyst ¹²

• microcystic

  • serous cystadenoma: usually head; 30% have a central scar

• cystic with a solid component

  • walled-off pancreatic necrosis

  • macrocystic tumors can also have a solid component

  • solid pseudopapillary tumor of the pancreas

  • primary ductal pancreatic tumor with cystic degeneration 

  • cystic degeneration of islet cell tumors (neuroendocrine tumors)

    • insulinoma

    • glucagonoma

• cystic teratoma

• metastases to pancreas

Retroperitoneal lesions (extrinsic to the pancreas) can mimic pancreatic cystic lesions, when close to the gland. Examples include:

• cystic lymphadenopathy (e.g. necrotic)

• duodenal diverticulum

Practical points

• the American College of Radiology (ACR) published guidelines on managing incidental cystic pancreatic lesions in 2017 ¹¹

• recent (c.2022) evidence reports that the incidence of pancreatic cancer in asymptomatic patients with cysts <2 cm is similar to background rates ¹⁴