Validation of combined carcinoembryonic antigen and glucose testing in pancreatic cyst fluid to differentiate mucinous from non-mucinous cysts

Gorris, M.; Dijk, F.; Farina, A.; Halfwerk, J.B.; Hooijer, G.K.; Lekkerkerker, S.J.; ... ; Hooft, J.E. van (2023)

Article / Letter to editor

Background: More accurate diagnosis of mucinous cysts will reduce the risk of unnecessary pancreatic surgery. Carcinoembryonic antigen (CEA) and glucose in pancreatic cyst fluid (PCF) can differentiate mucinous from non-mucinous pancreatic cystic neoplasms (PCN). The current study assessed the value of combined CEA and glucose testing in PCF. Methods: Cross-sectional validation study including prospectively collected PCF from patients undergoing endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) and pancreatic surgery. We performed laboratory measurements for CEA and glucose and measured glucose levels by a hand glucometer. Primary outcome was diagnostic accuracy evaluated by receiver operator curves (ROC), sensitivity, specificity, positive, and negative predictive value (PPV, NPV). Results: Overall, PCF was collected from 63 patients, including 33 (52%) with mucinous and 30 (48%) with non-mucinous PCN. Histopathology (n = 36; 57%), cytopathology (n = 2; 3%), or clinical and/or radiological diagnosis (n = 25; 40%) was used as reference standard. Combined CEA (cut-off >= 192 ng/ml) and laboratory glucose testing (cut-off < 50 mg/dL) reached 92% specificity and 48% sensitivity, whereas either positive CEA (cut-off >= 20 ng/ml) or glucose testing (cut-off < 50 mg/ dL) showed 97% sensitivity and 50% specificity. Sensitivity and specificity were 80% and 68% for CEA >= 20 ng/mL versus 50% and 93% for CEA >= 192 ng/mL (the conventional cut-off level). Laboratory and glucometer glucose both reached 100% sensitivity and 60% and 45% specificity, respectively. None of the biomarkers and cut-offs reached a PPV exceeding 90%, whereas both glucose measurements had a NPV of 100% (i.e., high glucose excludes a mucinous cyst). Conclusion: Combined CEA and glucose testing in PCF reached high specificity and sensitivity for differentiating mucinous from non-mucinous PCN. Glucose testing, whether alone or combined with the new CEA cut-off (>= 20 ng/mL), reached > 95% sensitivity for mucinous cysts, whereas only glucose reached a NPV > 95%.

• Pancreatic cystic neoplasms
• Pancreatic cyst fluid
• Carcinoembryonic antigen (CEA)
• Glucose
• Diagnostic accuracy
• Hepatobiliary tract and spleen
• Endoscopy
• Endoscopic ultrasound diagnostic and therapeutic

• All authors: Gorris, M.; Dijk, F.; Farina, A.; Halfwerk, J.B.; Hooijer, G.K.; Lekkerkerker, S.J.; Voermans, R.P.; Wielenga, M.C.; Besselink, M.G.; Hooft, J.E. van
• Date: 2023-01-19
• Journal: Surgical Endoscopy
• Volume: 37
• Pages: 3739 - 3746
• DOI: doi:10.1007/s00464-022-09822-6