Utility of Immunostains in Differentiating Gastric-Type Pancreatic Intraductal Papillary Mucinous Neoplasms (G-IPMNs) from Gastric and Duodenal Mucosal Contaminants in Pancreatic Endoscopic Ultrasound-Guided Fine Needle Aspirates.
Linjun Xie, Stefan Pambuccian, Stuart E Cameron, Steven Debol, Evin H Gulbahce, Anthony Rizzardi, Rachel Isaksson Vogel, Stephen C Schmechel. University of Minnesota, Minneapolis
Background: Due to their frequency and potential curability, IPMNs are a major target of pancreatic EUS-FNA. Their cytologic diagnosis may be difficult due to lack of cytologic atypia and resemblance to normal gastric (GM) or duodenal (DM) mucosal fragments, which are often contaminants of transgastric or transduodenal EUS-FNA. This study aimed to determine if immunohistochemical (IHC) stains may be useful to differentiate gastric-type IPMN (G-IPMN) from GM and DM.
Design: Tissue microarrays (TMAs) were constructed from 19 cases of resected G-IPMN, 20 GM, 20 DM and 20 benign pancreatic tissues. IHC stains AMACR (P504S), B72.3, CDX2, CK7, CK20, HepPar1, mCEA, MOC31, MUC1, p16 and villin were applied to TMA sections. The extent and intensity of staining were assessed on a 0-3+ scale for all stains, and digitized IHC staining intensity was determined for selected stains.
|Gastric mucosa (n=20)||Benign pancreatic tissue (n=20)||Duodenal mucosa (n=20)||IPMN Gastric type (n=19)|
|AMACR (P504s)||80% )||90%||100%||89%|
|MUC1||88% (n=16)||91% (n=11)||0 (n=9)||30% (n=10)|
|P16||5% F||95% F||0||89%|