Does EUS-FNA molecular analysis carry additional value when compared to cytology in the diagnosis of pancreatic cystic neoplasm? A systematic review

BackgroundEndoscopic ultrasonography with fine needle aspiration (EUS-FNA) has become an integral tool in the diagnosis of pancreatic cystic lesions (PCLs) and the analysis of molecular/DNA abnormalities might improve the accuracy of pre-operative diagnosis. A review was conducted of all studies using EUS-FNA aspirates of PCLs to assess the accuracy and added benefit that molecular analysis provides to cytological analysis. MethodsA systematic review of the literature was conducted using PRISMA guidelines and electronic databases: PubMed/SCOPUS/EMBASE/Cochrane/CINAHL. Surgical pathology was used as the definitive reference standard. The QUADAS-2 tool was used for quality assessment. ResultsIn total, 162 articles were identified; 12 articles met inclusion/exclusion criteria. Ten studies reported on cytology and 8 studies reported k-ras mutational analysis. 362 patients (of 1115 total) had surgical pathology available. The sensitivity and specificity of cytology was 0.42 and 0.99; the sensitivity and specificity of k-ras was 0.39 and 0.95; and the sensitivity and specificity of the combined test of cytology and k-ras was 0.71 and 0.88, respectively. Conclusionsk-ras mutational analysis used as an individual screening test has a poor diagnostic accuracy, as does cytology when used alone. The benefit comes with utilization in a combined fashion. More studies are needed to evaluate the correct sequence and utility of these tests for cyst differentiation.