The level of glucose in pancreatic cyst fluid is more accurate than carcinoembryonic antigen to identify mucinous tumors: A French multicenter study.

Background and objectives: Pancreatic cyst fluid level of glucose is a promising marker to identify mucinous from nonmucinous tumors, but the glucose assay has not yet been recommended. The objective of this study is to compare the diagnostic performances of pancreatic cyst fluid level of glucose and carcinoembryonic antigen (CEA).

Methods: In this French multicenter study, data of consecutive patients who underwent fine-needle aspiration of pancreatic cyst with intracyst glucose assay between 2018 and 2022 were retrospectively reviewed. The area under the receiver operating characteristic curve (AUROC) of glucose and corresponding sensitivity (Se), specificity (Sp), accuracy (Acc), positive predictive value (PPV), and negative predictive value (NPV) were calculated and compared with those of CEA. The best threshold of glucose was identified using the Youden index.

Results: Of the 121 patients identified, 81 had a definitive diagnosis (46 mucinous, 35 nonmucinous tumors) and were included for analysis. An intracystic glucose level <41.8 mg/dL allowed identification of mucinous tumors with better diagnostic performances (AUROC, 93.6%; 95% confidence interval, 87.2%-100%; Se, 95.3%; Sp, 91.2%; Acc, 93.5%; PPV, 93.2%; NPV, 93.9%) compared with CEA level >192 ng/mL (AUROC, 81.2%; 95% confidence interval, 71.3%-91.1%; Se, 41.7%; Sp, 96.9%; Acc, 67.6%; PPV, 93.8%; NPV, 59.6%) (P = 0.035). Combining values of glucose and CEA did not offer additional benefit in terms of diagnosis.

Conclusion: Our results confirm previously published data and support the use of pancreatic cyst fluid glucose for the identification of mucinous tumors when the definitive diagnosis remains uncertain.