Analysis Of The Learning Curve For Diagnosis Of Pancreatic Solid Mass By Endoscopic Ultrasound-Guided Fine-Needle Aspiration

Objective:Although endoscopic ultrasound-guided fine needle aspiration(EUS-FNA)is widely used in the diagnosis of pancreatic solid mass,up to date,little is known about how endoscopists with experience in Endoscopic ultrasonography(EUS)master and skillfully operate this endoscopic skill in this procedure.The purpose of this study is to explore the learning curve and clinical effect of EUS-FNA for pancreatic solid mass performed by one endoscopist with basic EUS scanning foundation but no previous EUS-FNA experience,so as to provide a reference for clinicians to better learn and apply EUS-FNA technology.Methods:The study retrospectively investigated consecutive 69 cases who underwent EUS-FNA procedure for pancreatic solid mass by a single endoscopist from March 2018 to March 2022.Cumulative sum(CUSUM)analysis was used to analyze procedure time and to fit the CUSUM learning curve.The goodness of fit was judged by R2.The cut-off point was determined and divided into learning,mastering and skilled stages according to the trend of the learning curve.The number of procedure cases that reached the stable level of EUS-FNA was analyzed.Procedure time(PT),lesion location and size,number of puncture needles,cytological and pathological diagnosis,and incidence of complications were compared at each stage of the learning curve.Value the diagnosis value of EUS-FNA to pancreatic solid mass through diagnostic accuracy,sensitivity and specificity.Results:The learning curve of EUS-FNA was divided into three stages according to the trend of EUS-FNA learning curve:initial learning,mastery and proficiency,with case 12 and case 25 as the cut-off points.The procedure time showed a continuous downward trend after case 25,and the endoscopist’s technical level reached a stable stage.There was no significant difference in lesion location and size,number of needle puncture and histopathological score among the 3 stages of the learning curve(P>0.05).The procedure time of stage 2 and 3 was shorter than that of stage 1,and there was a significant difference in procedure time between stage 1 and stage 3.The cytological diagnosis rate of stage 3 was higher than that of stage 1.The accuracy,sensitivity and specificity of EUS-FNA in the diagnosis of pancreatic solid mass were 86.96%,92.98%and 58.33%,respectively.Conclusion:For an endoscopist experienced with basic EUS skills,approximately 25 EUS-FNA cases of pancreatic solid mass need to be performed independently to achieve a stable level of this procedure.It was found that the procedure time decreased with the increase of the number of cases.There was no increase in the incidence of complications in the early stages of the learning curve compared to the later stages.After the learning phase of the learning curve,that is,after crossing the learning curve,endoscopists can perform the procedure stably for a long time.EUS-FNA has an important diagnostic value for pancreatic solid mass,which can provide pathological evidence for the diagnosis and treatment of the disease.It is a minimally invasive,safe,reliable and effective diagnostic method.