Prostaglandin E2: A Pancreatic Fluid Biomarker of Intraductal Papillary Mucinous Neoplasm Dysplasi

Abstract

Background With the increased frequency of diagnostic imaging, pancreatic cysts are now detected in >3% of American adults. Most of these are intraductal papillary mucinous neoplasms (IPMNs) with well-established but variable malignant potential. A biomarker that predicts malignant potential or dysplastic grade would help determine which IPMNs require removal and which can be observed safely. We previously reported that pancreatic fluid prostaglandin E2 (PGE2) levels might have promise as a predictor of IPMN dysplasia and we seek to validate those results in the current study. Study Design Pancreatic cyst/duct fluid was prospectively collected from 100 patients with IPMN undergoing pancreatic resection. Surgical pathology revealed 47 low-/moderate-grade, 34 high-grade, and 20 invasive IPMNs. The PGE2 levels were assessed by ELISA and correlated with IPMN dysplasia grade, demographics, clinical radiologic/pathologic variables, acute/chronic pancreatitis, and NSAID use. Results Mean pancreatic cyst fluid PGE2 levels in high-grade and invasive IPMNs were significantly higher than low-/moderate-grade IPMNs (3.5 and 4.4 pg/μL, respectively, vs 1.2 pg/μL; p < 0.0016). At a threshold of 1.1 pg/μL, PGE2 was 63% sensitive, 79% specific, and 71% accurate for detection of high-grade/invasive IPMNs. When tested in the subset of IPMN patients with preoperative pancreatic cyst fluid CEA >192 ng/mL, PGE2 at a threshold of 0.5 pg/μL demonstrated 78% sensitivity, 100% specificity, and 86% accuracy for detection of high-grade/invasive IPMN. Conclusions Our results validate pancreatic cyst fluid PGE2 as an indicator of IPMN dysplasia, especially in select patients with preoperative pancreatic cyst fluid CEA >192 ng/mL. The inclusion of PGE2/CEA in a diagnostic biomarker panel can facilitate more optimal treatment stratification of IPMN patients.