Cystic neoplasms of the pancreas and other cystic lesions, many of which cause “cyst-like” dilatations of the main or branch pancreatic ducts are collectively referred to as cystic lesions of the pancreas on cross-sectional imaging of the abdomen. The incidence of these cystic lesions increases with age. One autopsy study has demonstrated that up to a quarter of elderly individuals harbor cystic lesions of the pancreas at their demise.1 With the ever increasing use of computed tomography (CT) and magnetic resonance imaging (MRI), cystic lesions of the pancreas are being defined with progressively greater frequency, and an ever increasing number are asymptomatic at discovery.2,3 Some of these lesions will be malignant or have malignant potential at diagnosis, while others are clearly benign and may not warrant further surveillance. Resection of benign cystic pancreas lesions or those containing only carcinoma in situ leads to nearly universal survival, while surgery for invasive carcinoma associated with cystic neoplasms generally has a more favorable prognosis than the results for pancreatic ductal adenocarcinoma.4,5 Thus careful consideration must be given to the diagnosis and prognostic implications of these lesions.
An ideal diagnostic approach would allow for the resection of only those lesions with present or near-future risk of malignancy, while excluding from surgery those individuals with either benign lesions or a prohibitive operative risk, thus minimizing the potential occurrence of mortality and morbidity associated with the surgical treatment of these cystic lesions. Recent advancements in imaging by CT, MRI, and endoscopic ultrasonography (EUS), linked with refinements in the pathological understanding of cystic neoplasms of the pancreas have furthered this effort. History and clinical criteria, such as age, gender, presence of symptoms, location of the neoplasm within the pancreas, as well as, morphology by cross-sectional imaging and cyst fluid analysis by EUS with fine-needle aspiration (EUS-FNA), all may play a role in the diagnosis of pancreatic cystic neoplasms and assessment of the need for resection. A recent analysis using decision analysis with Markov modeling has indicated that for patients focused on overall survival, regardless of quality of life, surgery is optimal for branch duct lesions greater than 2 cm in size.6 For patients more focused on quality-adjusted survival, a 3-cm threshold is more appropriate for surgical intervention, except for the very elderly patients.
Pancreatic pseudocysts (or early postpancreatitis acute fluid collections) have been considered as the most common non-neoplastic cysts of the pancreas. Their diagnosis is aided by a history of acute or chronic pancreatitis.7 Congenital cysts are rare and include those associated with genetic diseases such as autosomal dominant polycystic disease,8 cystic fibrosis,9 and von Hippel-Lindau (VHL) disease.10,11 Lymphoepithelial cysts are rare benign lesions of the pancreas lined with squamous epithelium.12
Three cystic lesions make up 90% of the cystic neoplasms seen in the pancreas: serous cystic neoplasms (SCNs), mucinous cystic neoplasms (MCNs), and intraductal papillary mucinous neoplasms (IPMNs). SCNs rarely demonstrate ...