EUS-guided FNA for diagnosis of solid pancreatic neoplasms: a meta-analysis

BackgroundPreoperative diagnosis of solid pancreatic lesions remains challenging despite advancement in imaging technologies. EUS has the benefit of being a minimally invasive, well-tolerated procedure, although results are operator-dependent. The addition of FNA (EUS-guided FNA) provides samples for cytopathologic analysis, a major advantage over other imaging techniques.ObjectiveTo determine the diagnostic accuracy of EUS-FNA for pancreatic cancer.DesignThis is a meta-analysis of published studies assessing the diagnostic capability of EUS-FNA. Relevant studies were identified via MEDLINE and were included if they used a reference standard of definitive surgical histology or clinical follow-up of at least 6 months.Main Outcome MeasurementsData from selected studies were analyzed by using test accuracy meta-analysis software, providing a pooled value for sensitivity, specificity, diagnostic odds ratio, and summary receiver operating characteristic curve. Cytology results were classified as inadequate, benign, atypical, suspicious, or malignant. Predefined subgroup analysis was performed.ResultsThirty-three studies published between 1997 and 2009 were included, with a total number of 4984 patients. The pooled sensitivity for malignant cytology was 85% (95% confidence interval [CI], 84-86), and pooled specificity was 98% (95% CI, 0.97-0.99). If atypical and suspicious cytology results were included to determine true neoplasms, the sensitivity increased to 91% (95% CI, 90-92); however, the specificity was reduced to 94% (95% CI, 93-96). The diagnostic accuracy of EUS-FNA was enhanced in prospective, multicenter studies.LimitationPublication bias was not a significant determinant of pooled accuracy.ConclusionThis meta-analysis demonstrates that EUS-FNA is a highly accurate diagnostic test for solid neoplasms of the pancreas and should be considered when algorithms for investigating solid pancreatic lesions are being planned.