Intracystic Glucose Levels in Differentiating Mucinous From Nonmucinous Pancreatic Cysts A Systematic Review and Meta-analysis

Background: Mucinous pancreatic cysts are well reported to transform into pancreatic adenocarcinoma, whereas nonmucinous cysts are mostly benign with low risk for malignant transformation. Nonsurgical methods of differentiating mucinous and nonmucinous pancreatic cysts are challenging and entail a multi investigational approach. Low intracystic glucose levels have been evaluated in multiple studies for its accuracy in differentiating mucinous from nonmucinous cysts of the pancreas. Methods: Multiple databases were searched and studies that reported on the utility of intracystic glucose levels in diagnosing mucinous pancreatic cysts were analyzed. Meta-analysis was conducted using the random-effects model, heterogeneity was assessed by I (2)%, and pooled diagnostic test accuracy values were calculated. Results: Seven studies were included in the analysis from an initial total of 375 citations. The pooled sensitivity of low glucose in differentiating mucinous pancreatic cyst was 90.5% [95% confidence interval (CI): 88.1-92.5; I (2)=0%] and the pooled specificity was 88% (95% CI: 80.8-92.7; I (2)=79%). The sensitivity at a glucose cut-off of 50 was 90.1% (95% CI: 87.2-92.5; I (2)=0%) and the specificity was 85.3% (95% CI: 76.8-91.1; I (2)=76%). The sensitivity of glucose levels in pancreatic cyst fluid taken by endoscopic ultrasound guided fine-needle aspiration was 90.8% (95% CI: 87.9-93.1; I (2)=0%) and the specificity was 90.5% (95% CI: 81.7-95.3; I (2)=83%). The sensitivity of point-of-care glucometers was 89.5% (95% CI: 87.9-93.1; I (2)=0%) and specificity was 83.9% (95% CI: 68.5-92.6; I (2)=43%). Conclusions: Low glucose level at a cut-off of 50 mg/dL on fluid samples collected by endoscopic ultrasound guided fine-needle aspiration and analyzed by point-of-care glucometer achieves excellent diagnostic accuracy in differentiating mucinous pancreatic cysts.