Which EUS-based technique is best at detecting pancreatic cystic lesions?

Endoscopic ultrasound (EUS)-guided through-the-needle biopsy (TTNB) and EUS-needle-based confocal laser endomicroscopy (nCLE) appear to be better options for centres with relevant expertise and facilities when diagnosing pancreatic cystic lesions (PCLs), suggests a study.

The investigators conducted a comprehensive literature search for all comparative studies examining the accuracy of two or more modalities for PCL diagnosis.

Diagnostic efficacy for mucinous PCLs was the primary outcome, while secondary ones included diagnostic efficacy for malignant PCLs, diagnostic success rate, and adverse event rate. The diagnostic accuracy of each index was assessed in a network meta-analysis using the ANOVA model.

Forty studies with a total of 3,641 patients were included in the meta-analysis. EUS-nCLE and EUS-TNNB showed significantly higher network ranking of the superiority index when compared with other techniques for differentiating mucinous PCLs. Notably, EUS-TNNB was deemed to be the best technique for malignant PCL identification.

“The evidence was inadequate for EUS-nCLE diagnosing malignant PCLs and contrast-enhanced harmonic EUS diagnosing both mucinous and malignant PCLs,” the investigators said.

In the diagnosis of mucinous PCLs, glucose demonstrated high sensitivity but low specificity, while molecular analysis (KRAS, GNAS, and KRAS + GNAS mutations) exhibited high specificity but low sensitivity. No satisfactory results were obtained during the assessment of the efficiency of pancreatic cyst fluid (PCF) biomarkers in identifying malignant PCLs.

“Further studies are urgently required for further improving PCF biomarkers and validating the diagnostic performance of the index techniques,” the investigators said.