The Application Of Endoscopic Ultrasound-guided Fine Needle Aspiration/biopsy Technique In The Differential Diagnosis Of Pancreatic Solid Lesions

Patients with pancreatic cancer have a poor prognosis and a high malignant degree.Therefore,rapid and correct diagnosis of a pancreatic mass is required to guide subsequent patient management.Along with the advance of medical technology,there are more and more imaging methods to diagnose the pancreatic malignant masses,including traditional imaging examination,for example: abdominal ultrasound,CT,MRI,also includes new imaging examination,such as: PET-CT.With the development of EUS,it is playing an increasingly important role in the diagnosis of pancreatic solid lesions.In addition,with the help of EUS-FNA and EUS-FNB,cytological and histological samples can be obtained in the diagnosis of pancreatic malignant tumor,which further improve the diagnostic accuracy of solid pancreatic malignant lesions compared with solely EUS.At present,there is relatively little comparative research on the accuracy of the diagnosis of pancreatic malignant lesions by imaging examination and EUS-FNA/FNB.At the same time,there is still a great controversy about the accuracy of EUS-FNA and EUS-FNB in the diagnosis of the pancreatic malignancy.Further study deserves to be explored whether EUS-FNB can improve the diagnostic accuracy of pancreatic malignancy.Therefore,the study includes two parts.The first part: EUS-FNA/FNB and enhanced CT,MRI and PET-CT in the diagnosis of pancreatic solid malignant lesions.Background and Aims: There are still exist great differences on the accuracy of the diagnosis of pancreatic malignant lesions by imaging examination and EUS-FNA/FNB in the different literature reports,so this study is to explore EUS-FNA/FNB and enhanced CT,MRI and PET in the diagnosis accuracy of pancreas solid malignant lesions,to analyze the advantages of various inspection methods and guide clinical decision-making and further treatment.Methods: This study involved a retrospective cases of all EUS-guided sampling performed between November 2012 and November 2016.A total of 254 cases of EUS-FNA were included,including 256 pancreatic lesions.159 patients were suspected with pancreatic malignant by enhanced CT and performed EUS-FNA.89 patients were suspected with pancreatic malignant by enhanced MRI and performed EUS-FNA.34 patients were suspected with pancreatic malignant by PET-CT and performed EUS-FNA.168 cases of EUS-FNB were included,including 171 pancreatic lesions.107 patients were suspected with pancreatic malignant by enhanced CT and performed EUS-FNB.49 patients were suspected with pancreatic malignant by enhanced MRI and performed EUS-FNB.20 patients were suspected with pancreatic malignant by PET-CT and performed EUS-FNB.The clinical medical data including patients characteristics,clinical follow-up,as well as pathological results and final diagnosis were collected and analyzed.Accuracy,sensitivity,specificity,positive predictive values(PPVs),and negative predictive values(NPVs)for the pancreatic masses were reviewed and compared.Results: Diagnostic specificity and PPVs of pancreatic solid malignant lesions for EUS-FNA were significantly higher than that of enhanced CT and enhanced MRI,and diagnostic specificity and PPVs of pancreatic solid malignant lesions for EUS-FNB were significantly higher than that of enhanced CT.There were no significant differences in the accuracy,sensitivity,specificity,PPVs,or NPVs for the EUS-FNA/FNB and PET-CT in the diagnosis of pancreatic malignancy.Conclusion: Compared with the enhanced CT and MRI,the specificity and PPVs of EUS-FNA in the diagnosis of pancreatic solid masses were significantly higher.Compared with the enhanced CT,the specificity and PPVs of EUS-FNB in the diagnosis of pancreatic solid masses were significantly higher.EUS-FNA/FNB help to reduce the misdiagnosis rate of pancreatic benign lesions.There were no significant differences in the accuracy,sensitivity,specificity,PPVs,or NPVs for the EUS-FNA/FNB and PET-CT in the diagnosis of pancreatic malignancy.The second part: Comparison of 22 gauge aspiration and 22 gauge biopsy needles in the differential diagnosis of malignant pancreas solid masses.Background and Aims: To overcome the limitations of using a cytological specimen alone for the diagnosis of challenging pancreatic lesions,biopsy needles have been developed to procure histological specimens during endoscopic ultrasound(EUS),especially for the discrimination of several specific pancreatic tumors requiring adequate histological samples,such as pancreatic neuroendocrine neoplasms(PNENs),solid-pseudopapillary neoplasms(SPN),and pancreatic lymphoma.The aim of this study was to compare the diagnostic yield of 22-gauge(G)aspiration and 22 G biopsy needles for sampling pancreatic masses.Methods: We conducted a retrospective study of all EUS-guided sampling performed between November 2012 and November 2016.In total,422 cases sampled with a 22 G aspiration needle(N=254)or a 22 G biopsy needle(N=168)were recruited for this study.An on-site cytopathologist was not present during the procedure.The cytological and histological specimen quality analyses,technical characteristics,accuracy,sensitivity,specificity,positive predictive values(PPVs),and negative predictive values(NPVs)for the pancreatic masses were reviewed and compared.Results: There was no significant difference in the procurement of adequate histological specimens(75.0% vs.79.5%;P=0.277)or the presence of diagnostic histological specimens(71.3% vs.77.4%;P=0.155)between the FNA and FNB groups,respectively.There were also no significant differences in the accuracy,sensitivity,specificity,PPVs,or NPVs of the cytological,histological,and overall analyses for the FNA and FNB groups in the diagnosis of pancreatic malignancy.However,22 G biopsy needles demonstrated a better histological diagnostic yield in the discrimination of pancreatic adenocarcinoma and other non-adenocarcinoma pancreatic neoplasms than 22 G aspiration needles(69.8% vs.57.9%,P=0.033).Conclusions: The 22 G biopsy needles were technically feasible,safe,efficient,and comparable to the standard 22 G aspiration needles in patients with pancreatic masses in the absence of an on-site cytopathologist.However,the 22 G biopsy needles demonstrated a better histological diagnostic yield in the differentiation between pancreatic adenocarcinoma and non-adenocarcinoma pancreatic neoplasms.