Cytologic Evaluation of Cystic Pancreatic Lesions (CPL): Comparison of EchoBrush Vs. Standard EUS-FNA Techniques in a Blinded Prospective Study

Abstract

Background: Cystic pancreatic lesions (CPL) are associated with a potential for malignant transformation. EUS-guided FNA is a widely used method for evaluating these lesions, but has limited sensitivity. Recently, in a non blinded pilot study we have shown that cytology samples obtained by through-the-needle cytologic brush at the time of EUS (EchoBrush, Cook Endoscopy, Winston-Salem, NC) has superior diagnostic yield compared to conventional FNA. (Al-Haddad et al, 2007) Objectives: To evaluate the cytologic yield of EchoBrush versus EUS-FNA in a blinded prospective study. Methods: In this ongoing study 22 consecutive patients (age 43-94yrs, mean 69) with CPL were included. All cysts were sampled by standard EUS-FNA (50% of cyst volume) followed by EchoBrush cytology, then by aspiration of the remaining fluid. Fluid samples were separately submitted (EUS-FNA and EchoBrush) and were read by a study pathologist who was unaware of the sampling technique and findings in the corresponding paired sample. Cytologic specimens were evaluated for the presence of mucinous epithelium/intracellular mucin (ICM) and grade of dysplasia. The two methods were compared for presence of mucinous epithelium and grade of dysplasia. Results: ICM was detected in total 17/22 patients. ICM was detected in 16/22 patients using EchoBrush and 6/22 patients using EUS-FNA. (Table 1) For 6 patients ICM was detected in the EchoBrush sample alone, and for 1 patient ICM was detected in the EUS-FNA sample alone. For 17 patients with mucinous epithelium, high grade dysplasia was detected in 2 cases by EchoBrush alone. Conclusion: This study suggests that a higher frequency of cytologically diagnostic specimens are obtained using EchoBrush vs. EUS-FNA. Table 1Yield of EchoBrush and EUS-FNA for intracellular mucin in CPL EchoBrush (N = 22) Intracellular Mucin + Intracellular Mucin − EUS/FNA (N = 22) Intracellular Mucin + 5 1 Intracellular Mucin − 11 5 Open table in a new tab