CT scan showing a large cystic tumour arising from the pancreatic tail in a young woman

Cystic tumours are tumours that contain fluid. Small cysts (i.e. tiny pockets of fluid) may be seen in the pancreas on an ultrasound, CT or MRI scan. These may cause alarm but often are of little significance. Cysts that are less than 3cm in diameter and do have any worrying features (such as solid nodules in the wall of the cyst, or a swollen pancreatic duct, or a rise in the serum level of the tumour marker CA19-9) just need surveillance with an annual scan, at least for a few years. Cysts over 3cm in diameter or with worrying features may need evaluation with Endoscopic ultrasound and fine-needle aspiration (EUS + FNA). Cystic tumours of the pancreas may be Serous (filled with watery fluid) or Mucinous (filled with mucus-like fluid).

Serous tumours

Serous cystadenomas are typically found in older women, and are clusters of multiple small cysts, almost like scrunched up bubble-wrap. They are benign, and surgical removal is warranted only if there are symptoms.

Mucinous tumours

These may be benign but have a potential for turning malignant, and are best removed surgically if possible. There are two types: Mucinous Cystic Neoplasms (MCN) and Intraductal Papillary Mucinous Neoplasms (IPMN). Mucinous tumours arising within the main pancreatic duct are often multiple and have a greater tendency to prove malignant. Thick mucus seen extruding from the opening of the duct at ERCP is diagnostic of a main duct tumour. Mucinous tumours can be confused with pseudocysts. Endoscopic ultrasound and aspiration of some of the cyst fluid can be a useful test. The fluid is usually tested for tumour cells, amylase levels and CEA levels (CEA is a tumour marker).

Solid pseudopapillary tumour is a rare, slowly-progressive but malignant tumour, seen in women in the child-bearing age, and manifests as a large, part-solid, part-cystic tumour. The term Cystadenocarcinoma is often used to describe an adenocarcinoma (see below) that has partly liquefied at its centre.

For more information on the surgical treatment of these tumours, please look at the page on Pancreas Operations: FAQ (which you can download as an information booklet), and in the Pancreatic Cancer page at What is the treatment of Pancreatic Cancer.