How Good Is EUS-FNA in Diagnosing the Correct Etiology for a Solid Pancreatic Mass? A Meta-Analysis and Systematic Review

Abstract

Background: The published data on accuracy of EUS-FNA in diagnosing the correct etiology for a solid pancreatic mass has been varied. Detecting the correct etiology for a pancreatic mass help in triaging patients for appropriate therapies and might obviate the need for invasive surgery. Aim: To evaluate the accuracy of EUS-FNA in diagnosing the correct etiology for a solid pancreatic mass. Method: Study Selection Criteria: EUS-FNA studies with a gold standard (either confirmed by surgery or appropriate follow-up) were selected. Data collection & extraction: Articles were searched in Medline, Pubmed, Ovid journals, Cumulative index for nursing & allied health literature, International pharmaceutical abstracts, old Medline, Medline nonindexed citations, and Cochrane Central Register of Controlled Trials & Database of Systematic Reviews. Two reviewers independently searched and extracted data. The differences were resolved by mutual agreement. Statistical Method: Meta-analysis for the accuracy of EUS was analyzed by calculating pooled estimates of sensitivity, specificity, likelihood ratios, and diagnostic odds ratio. Pooling was conducted by both Mantel-Haenszel method (fixed effects model) and by the DerSimonian Laird method (random effects model). The heterogeneity of studies was tested using Cochran's Q test based upon inverse variance weights. Results: Initial search identified 3610 reference articles, of these 360 relevant articles were selected and reviewed. Data was extracted from 69 studies (N= 6493) which met the inclusion criteria. Pooled sensitivity of EUS-FNA in diagnosing the correct etiology for solid pancreatic mass was 86.9% (95% CI: 85.9 - 87.9). EUS-FNA had a pooled specificity of 95.9% (95% CI: 94.9 - 96.7). The positive likelihood ratio of EUS was 14.7 (95% CI: 9.4 - 22.9) and negative likelihood ratio was 0.18 (95% CI: 0.15 - 0.23). The diagnostic odds ratio, the odds of having correct histologic etiology of pancreatic mass in positive as compared to negative EUS-FNA studies was 93.5 (95% CI: 58.6 - 149.1). All the pooled estimates calculated by fixed and random effect models were similar. SROC curves showed an area under the curve of 0.95. Egger bias, an indicator for publication bias, was 0.59 (95% CI = -0.23 to 1.43, p = 0.1525), and confirmed no publication bias. The p for chi-squared heterogeneity for all the pooled accuracy estimates was > 0.10. Conclusions: EUS-FNA is an excellent diagnostic tool to detect the correct etiology for solid pancreatic mass. When available, EUS-FNA should be strongly considered as the first diagnostic tool for sampling solid pancreatic lesions to guide patient management.