Nonmucinous Cystic Lesions of the Pancreas

Abstract

Context.— Pancreatic cystic lesions are increasingly diagnosed. Among other criteria, they are often distinguished in mucinous versus nonmucinous cysts. Mucinous pancreatic cystic lesions have received increasing attention, especially those known as precursors of pancreatic ductal adenocarcinoma. However, the group of nonmucinous cystic lesions of the pancreas includes numerous entities that may pose a diagnostic challenge. Their accurate diagnosis and classification are crucial for adequate patient management. Objective.— To review the spectrum of nonmucinous cystic lesions of the pancreas, taking into consideration their epidemiology and typical clinical context, their characteristic gross morphology and histomorphology, as well as their immunohistochemical and molecular profile. Data Sources.— Literature was searched and reviewed with MEDLINE via PubMed. Macroscopic and microscopic images were obtained from the archives of the Institute of Pathology, Heinrich Heine University and University Hospital of Duesseldorf, Germany. Conclusions.— Nonmucinous cysts of the pancreas comprise numerous, mostly rare entities displaying different biological behaviors. The most frequent are serous cystic neoplasms, solid-pseudopapillary neoplasms, cystic neuroendocrine tumors, and pancreatitis-associated pseudocysts. Accurate diagnosis can be achieved if characteristic clinical context, histomorphology, and immunoprofile are taken into account.

Pancreatic Cystic Lesions: A Focused Review on Cyst Clinicopathological Features and Advanced Diagnostics

“…EUS-FNA of cyst fluid with molecular analysis and nCLE for in vivo endomicroscopy, when indicated (generally PCLs ≥ 2 cm diameter), collectively approach a high (>90%) accuracy for the diagnosis and risk stratification of PCLs [2][3][4][5]9,23]. Data sources [1,3,9,13,14,52,66,72]. * Based on surgical series [10][11][12].…”

“…Other rare pancreatic cystic lesions not discussed in this review include intraductal oncocytic neoplasm (IOPN), intraductal tubulopapillary neoplasm (ITPN), acinar cystic transformation of the pancreas, among others [13,52,107].…”

“…According to recent surgical series of PCLs [10][11][12], the most resected PCLs are mucinous neoplasms: IPMNs (45% of all resected PCLs) and mucinous cystic neoplasm (MCN, 16%). The most frequently resected non-mucinous neoplasms include serous cystic neoplasms (SCN, 16%), cystic neuroendocrine tumors (cNET, 5%), and solid pseudopapillary neoplasm (SPN, 3%) [13]. In this review, for each of these and other commonly encountered PCLs, the definition, epidemiology, location, macroscopic, endomicroscopic, histologic features, and molecular alterations will be reviewed systematically to help with the differential considerations and the ultimate construction of the final diagnosis.…”