Impact of macroscopic on-site evaluation on the diagnostic outcomes of endoscopic ultrasound-guided fine-needle aspiration.

BACKGROUND: Endoscopic ultrasound (EUS)-guided tissue acquisition is the preferred modality for diagnosing pancreatic lesions and mediastinal and abdominal lymph nodes. Rapid on-site cytologic evaluation improves the diagnostic outcome of EUS-guided fine-needle aspiration (FNA) but is unavailable at many centers. Alternatively, macroscopic on-site evaluation (MOSE) may improve the diagnostic outcome of EUS-FNA, but data are limited. Hence, the present study was conducted to assess the efficacy of MOSE in improving adequacy and accuracy.

METHODS: We retrospectively analyzed data of consecutive patients with pancreatic or lymph nodal lesions undergoing EUS-guided FNA at a tertiary care center from December 2020 to December 2022. The study's primary outcomes were adequacy and diagnostic accuracy of the EUS-guided tissue acquisition, with secondary analysis of predictors of adequacy and accuracy.

RESULTS: Data from 124 patients (44.4% male, median age: 54 years) who underwent EUS-FNA were included in the present analysis. The presence of macroscopic visible core (MVC) on MOSE was reported in 93/124 (75%) cases. An adequate sample for histopathological or cytological examination was obtained in 110/124 (88.7%) cases, while the diagnostic accuracy was 85.5%. On multivariate analysis, the absence of MVC on MOSE was found to be the independent negative predictor of both adequacy (OR 0.092, 95% CI: 0.024-0.349) and accuracy (OR 0.175, 95% CI: 0.057-0.536).

CONCLUSION: The presence of MVC on MOSE can be an indicator of specimen adequacy and can improve the diagnostic yield of EUS-FNA.