S1296 Identifying IPMN and Pancreatic Cyst That Develop Conventional Pancreatic Cancer

Abstract

based cytology in differentiating mucinous versus nonmucinous PCL. Methods: MEDLINE, SCOPUS, Cochrane, and CINAHL Plus databases were used to identify studies in which results of EUS-FNA based cytology of a pancreatic cyst were compared with the results of an acceptable criterion standard, including surgical biopsy or surgical excision histology of a pancreatic cyst. Two independent reviewers extracted the standardized data. The DerSimonian-Liard random effects model was used to estimate the pooled sensitivity, specificity, likelihood, and diagnostic odds ratio (DOR). A summary receiver operating characteristic (SROC) curve was also constructed. All potential sources of heterogeneity amongst the studies were explored by subgroup and meta-regression analyses. Results: A total of 701 patients with EUS-FNA cytology of PCL were examined from 14 distinct studies that satisfied our inclusion criteria. The pooled sensitivity of EUS-FNA based cytology in diagnosing mucinous cystic lesions (MCL) was 0.65 (95% CI, 0.59-0.70) and pooled specificity was 0.92 (95% CI, 0.89-0.95). The positive likelihood ratio for diagnosing MCL by EUS-FNA based cytology was 4.93 (95% CI, 1.35-18.08) and the negative likelihood ratio was 0.46 (95% CI, 0.27-0.80). The area under the curve (AUC) was 0.87. The P value for X2 heterogeneity for all the pooled estimates was >.05 suggesting significant heterogeneity amongst the studies. Heterogeneity is probably caused by factors that were inadequately reported in primary studies and, therefore, could not be explored in this meta-analysis. Conclusion: EUS-FNA based cytology has overall low sensitivity but excellent specificity in differentiating mucinous versus non-mucinous pancreatic cystic lesions. Thus EUS-FNA based cytology should be the investigation of choice to exclude the possibility of mucinous cystic lesion while evaluating pancreatic cystic lesions. The combine role of EUS morphology, FNA based cytology, and cyst fluid analysis for potential molecular markers needs further investigation.