Endoscopic Ultrasound-Guided Fine Needle Aspiration with On-site Determination of Cytological Adequacy by Endoscopists

Background: On-site determination of cytological adequacy increases the diagnostic accuracy of EUS-FNA. However it is impossible in many centers and the EUS operators increase the number of pass. Some endoscopists themselves perform on-site determination of cytological adequacy by using Diff-Quik stain, and assess the adequacy of specimens. Aims: This study was performed to evaluate the usefulness of EUS-FNA with on-site determination of cytological adequacy by endoscopists in the absence of a cytopathologist. Patients & Methods: Used were 61 specimens from 49 FNAs (48 patients) that were quite adequate for cytological evaluation. 1) EUS-FNA was performed using an Olympus linear array echoendoscope, and manually operated needles. 2) The cellularity was estimated before Diff-Quik stain. 3) The specimens were air-dry fixed and stained with Diff-Quik stain by endoscopist and others fixed in ethyl alcohol were stained with H & E. 4) Endoscopists performed on-site determination of cytological adequacy, and ended specimen collection by the result of Diff-Quik stain. 4) The final pathologic diagnosis was made on the basis of H & E, Giemsa, and Diff-Quik staining. Results: 1) The specimen collection rate was 100% (61/49). 2) The average number of needle passes was 3.11 (range, 1 to 8) 3) Sensitivity was 95% (38/40) and specificity 44.44% (4/9); positive predictive value was 88.37% (38/43) and negative 66.67% (4/6); accuracy was 85.71% (42/49). 4) There were no remarkable complications. Conclusions: For accurate diagnosis, on-site determination of cytological adequacy should be performed during EUS-FNA even if no cytopathologist is present. Additionally, if endoscopists bring up a sense of discrimination for Diff-Quik stained specimens, diagnostic accuracy might be enhanced more, and the number of needle passes would be minimized.

Key words: EUS-FNA, On-site determination, Endoscopist