Feasibility of endoscopic ultrasound (EUS) guided fine needle aspiration (FNA) and biopsy (FNB) with a new slim linear echoendoscope

Background: Endoscopic ultrasound (EUS) guided fine needle aspiration (FNA) and biopsy (FNB) is considered a very accurate and safe tool for sampling extra-intestinal tumors. Standard echoendosocopes for FNA/FNB are large with a sharpened tip that can be associated with complications. A new slim linear echoendoscope have been developed trying to overcome this limitation. Aim: Of the present study was to evaluate the feasibility; safety and diagnostic yield of this newly developed slim echoendoscope for performing EUS-guided FNA/FNB. Methods: A pilot observational study was performed. Consecutive patients submitted for a EUS-FNA/FNB were prospectively included in the study. Patients underwent EUS procedure using the new slim linear PENTAX-echoendoscope. Tissue acquisition was done with standard and histology needles. Feasibility and diagnostic yield were evaluated. A descriptive analysis was performed. Results: 87 patients were included (mean age 66.7 years (range 24-90 years), 45 male. Mean size was of lesions sampled were 33.43 ± 20.8 mm. Esophagus intubation and access to the second portion of the duodenum (D2) were considered easy in all 87 cases (100%). Nineteen procedures (21.8%) were performed from the esophagus, 42 (48.3%) from the stomach, 22 (25.3%) cases from duodenal bulb, and 4 (4.6%) cases from D2. EUS-FNB was feasible in 85 cases (97.7%), failed in 2 pancreatic lesions accessed from D2. Diagnostic yield was 86.21% (95%CI 77.4-91.9) in the intention-to-treat analysis and 88.24% (95%CI 79.7-93.5) in per-protocol analysis. There were no complications related to the technique. Conclusion: Performing a EUS-FNA/FNB with the newly designed slim scope is feasible and safe for cyto-histopathology diagnosis of intra-intestinal and extra-intestinal mass lesions.