The evolving role of EUS‐guided tissue acquisition

Abstract

The introduction of endoscopic ultrasound‐guided fine‐needle aspiration into clinical practice was a pivotal moment for diagnostic gastrointestinal endoscopy. It facilitates the ease of tissue acquisition from previously inaccessible sites. The performance characteristics of cytological diagnosis are excellent. However, there remain areas of inadequacies. These include procedural inefficiencies such as the need for rapid on‐site cytological evaluation or macroscopic on‐site evaluation, the crucial role of histology for diagnosis in specific conditions, the issue of sampling errors and the need for repeat procedures, and the shift towards personalized medicine, which requires histology, immunohistochemical studies, and molecular analysis. The original Trucut biopsy needle had been cumbersome to use, but the recent introduction of newer‐generation biopsy needles has transformed the landscape, such that there is now a greater focus on tissue acquisition for histological assessment. Concomitant technological advances of endoscopic ultrasound processors enabled higher‐resolution imaging, and facilitated image enhancement using contrast harmonic endoscopic ultrasound and endoscopic ultrasound elastography. These techniques can be used as an adjunct to guide tissue acquisition in challenging situations. There is ongoing research on the use of artificial intelligence to complement diagnostic endoscopic ultrasound and the early data are promising. Artificial intelligence may be especially important to guide clinical decision‐making if biopsy results are nondiagnostic.

Rapid on‐site evaluation by endoscopists: Another option to improve the diagnostic yield of EUS‐FNA of solid pancreatic lesions

“…There was no significant difference in specificity, positive, or negative predictive values. Consistent with other studies, the diagnostic yield was higher with combined cyto‐histological assessment 1 . The provisional cytological diagnosis provided by endoscopists was consistent with the final reported diagnosis by pathologists in 89 of 97 self‐ROSE cases.…”

“…Consistent with other studies, the diagnostic yield was higher with combined cyto-histological assessment. 1 The provisional cytological diagnosis provided by endoscopists was consistent with the final reported diagnosis by pathologists in 89 of 97 self-ROSE cases. Of the eight discrepant cases, three negative self-ROSE cases were malignant while five positive self-ROSE cases were benign when assessed by pathologists.…”

“…Options to optimize its diagnostic yield include the use of rapid on-site evaluation (ROSE) by cytopathologist or cytotechnician to confirm specimen adequacy, a pre-determined minimum number of needle passes if ROSE is not available, macroscopic on-site quality evaluation (MOSE) by the endoscopist to ensure at least 4 mm of macroscopic visible core tissue, and the use of biopsy needles. 1 In many institutions, it is not logistically feasible to have a cytopathologist or cytotechnician on site whenever EUS-FNA is performed. In addition, biopsy needles are more costly than FNA needles, or may not be available.…”

“…Endoscopic ultrasound (EUS)‐guided fine needle aspiration/biopsy (EUS‐FNA/FNB) of solid pancreatic lesions enables cytological/histological diagnosis to guide treatment strategy. Options to optimize its diagnostic yield include the use of rapid on‐site evaluation (ROSE) by cytopathologist or cytotechnician to confirm specimen adequacy, a pre‐determined minimum number of needle passes if ROSE is not available, macroscopic on‐site quality evaluation (MOSE) by the endoscopist to ensure at least 4 mm of macroscopic visible core tissue, and the use of biopsy needles 1 . In many institutions, it is not logistically feasible to have a cytopathologist or cytotechnician on site whenever EUS‐FNA is performed.…”

Immune Checkpoint Inhibitor-induced Pancreatitis with Pancreatic Enlargement Mimicking Autoimmune Pancreatitis: A Case Report and Review of the Literature

“…Recently, an EUS-fine needle biopsy needle was shown to be useful for obtaining sufficient histological specimens for further histological examinations ( 43 , 44 ). One of the reasons for the delayed understanding of the pathogenesis of ICI-induced pancreatitis may be the lack of histological material for the evaluation.…”