Endoscopic Ultrasound-guided Fine Needle Aspiration For Pancreatic Lesions And Lymph Nodes

BACKGROUNDEndoscopic ultrasound-guided fine-needle aspiration(EUS-FNA)is a minimally invasive technology commonly used in digestive diseases.For EUS-FNA has the advantages of low risk,small trauma and high accuracy,it has become an important diagnostic method for gastrointestinal tract and its surrounding lesions,especially for pancreatic lesions and lymph nodes which conventional interventional methods are difficult to obtain cytopathology or histopathology diagnosis.AIM1.To understand the application of EUS-FNA for pancreatic lesions,evaluate the cytological diagnostic capacity and sample quality of the slow-pull technique,compare them with different suction techniques and to explore the optimal suction technique.2.To understand the application of EUS-FNA for lymph nodes and evaluate the diagnostic ability and clinical impact of EUS-FNA for mediastinal and abdominal lymphadenopathy.METHODS1.102 patients with pancreatic solid lesions who underwent EUS-FNA with 22-gauge needles were retrospectively evaluated.EUS-FNA diagnosis was based on a cytological examination,and final diagnosis was based on a comprehensive standard of cytological diagnosis,surgical pathology and clinical or imaging follow-up.Cytological specimens were characterized for cellularity and blood contamination.The cytological diagnostic capacity and sample quality of the slow-pull technique and suction techniques with 5-mL/10-mL/20-mL syringes were analyzed.2.30 patients who underwent EUS-FNA for mediastinal or abdominal lymphadenopathy were retrospectively reviewed.EUS-FNA diagnosis was based on a cytological/histological examination,and final diagnosis was based on a comprehensive standard of cytological diagnosis,surgical pathology and clinical or imaging follow-up.The diagnostic ability and clinical impact of EUS-FNA were analyzed.RESULTS1.In EUS-FNA for pancreatic lesions,the accuracy and sensitivity of the slow-pull technique were significantly higher than those of the suction techniques using 5-mL(P=0.03,P=0.014),10-mL(P=0.005;P=0.006)and 20-mL syringes(P=0.01,P=0.01).Blood contamination was significantly lower in the slow-pull technique than in the suction techniques with 10-mL(P=0.001)and 20-mL syringes(P=0.007),but there was no statistical difference when the slow-pull technique compared with 5-ml(P=0.135).There was no statistical difference of the four different suction methods in sample cellularity.2.In EUS-FNA for lymph nodes,the total diagnostic accuracy,sensitivity,specificity,PPV(positive predictive value)and NPV(negative predictive value)of EUS-FNA was 96.7%,94.7%,100%,100%and 91.7%,respectively.Compared with the combination of cytology and histology examination,the accuracy(96.7%VS 73.3%,P=0.026)and sensitivity(94.7%VS 57.8%,P=0.019)of cytology examination were significantly lower.Immunohistochemistry stains were performed in 12 neoplastic cases,and it was found to be contributory in 11(91.7%)cases.The diagnosis of EUS-FNA had positive impact on clinical decisions in 27 patients(90.0%).CONCLUSION1.The slow-pull technique may increase the cytological diagnostic accuracy and sensitivity with slight blood contamination during EUS-FNA when using 22-gauge needles for solid pancreatic masses.2.EUS-FNA is an effective approach for the diagnosis of mediastinal and abdominal lymphadenopathy,and its result has a positive impact on clinical decisions.The combination of cytology and histology examination and application of ancillary techniques,such as immunohistochemistry stains,can improve the diagnostic ability of EUS-FNA.