Endoscopic ultrasound-guided fine needle aspiration in diagnosis of cystic pancreatic lesions

Abstract Background and study aims pancreatic cysts are commonly found lesions and proper diagnosis is very important for planning further management. The study aims to evaluate the role of cyst fluid amylase and tumour markers as cancer antigen (CA 19-9) and carcinoembryonic antigen (CEA) in addition to mucin stain in diagnosing pancreatic cysts and differentiating malignant from benign lesions. Patients and methods This prospective study was conducted on 184 patients diagnosed to have pancreatic cystic lesions from January 2013 to January 2018. Fluid analysis for CA 19-9, CEA, amylase, mucin stain and cytopathology were done. We compared these data with the final diagnosis based on histopathology after surgical resection, positive cytopathology and long period of follow up of the patients for at least 18 months. Results The highest AUC was that of cystic CEA with cut-off value of 160 ng/ml; it had a sensitivity of 60.4% and a specificity of 85%. The best cut-off value for cystic CA 19-9 was 1318 U/ml with a sensitivity of 64.1% and a specificity of 68.1%. The cut-off value of cyst amylase level was 5500 U/L, with 84.2% sensitivity and 37.1% specificity. The sensitivity of mucin stain in detecting mucinous cystic neoplasm was 85.45%, specificity was 86.05% with accuracy 85.87%. Conclusion Cyst fluid analysis by investigating amylase, mucin, CA 19-9, CEA and EUS examination improves the diagnosis of different pancreatic cysts.