Retrospective Cohort Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Endosc. Aug 16, 2020; 12(8): 212-219
Published online Aug 16, 2020. doi: 10.4253/wjge.v12.i8.212
Improved diagnostic yield of endoscopic ultrasound-fine needle biopsy with histology specimen processing
Lawrence Ku, Mohammad A Shahshahan, Linda A Hou, Viktor E Eysselein, Sofiya Reicher
Lawrence Ku, Mohammad A Shahshahan, Linda A Hou, Viktor E Eysselein, Sofiya Reicher, Department of Medicine, Division of Gastroenterology and Hepatology, Harbor-UCLA Medical Center, Torrance, CA 90509, United States
Author contributions: Ku L and Reicher S contributed to study design, data collection, data analysis, manuscript drafting, manuscript revision, and final approval of the manuscript; Shahshahan MA contributed to data collection, data analysis, manuscript drafting, and manuscript revision; Hou LA and Eysselein VE contributed to data collection, manuscript drafting, and manuscript revision.
Supported by the National Center for Advancing Translational Sciences through University of California, Los Angeles Clinical and Translational Science Institute Grant, No. UL1TR001881-01.
Institutional review board statement: The study was approved by the Institutional Review Board, No. 31297-01.
Informed consent statement: Not applicable to this retrospective cohort study.
Conflict-of-interest statement: Sofiya Reicher is a consultant for Boston Scientific; all other authors have no conflicts of interest.
Data sharing statement: Technical appendix, statistical code, and dataset available from the corresponding author at sreicher@dhs.lacounty.gov. Consent was not obtained, but the presented data are anonymized and risk of identification is low.
STROBE statement: The authors have read the STROBE Statement checklist of items, and the manuscript was prepared and revised according to the STROBE Statement checklist of items.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Sofiya Reicher, MD, Associate Professor, Attending Doctor, Director, Department of Medicine, Division of Gastroenterology and Hepatology, Harbor-UCLA Medical Center, 21840 South Normandie Ave, Ste 850, Torrance, CA 90509, United States. sreicher@dhs.lacounty.gov
Received: March 26, 2020
Peer-review started: March 26, 2020
First decision: April 22, 2020
Revised: June 4, 2020
Accepted: July 18, 2020
Article in press: July 18, 2020
Published online: August 16, 2020
Processing time: 139 Days and 9.3 Hours
Abstract
BACKGROUND

Endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) has emerged as a safe, efficacious alternative to fine needle aspiration (FNA) for tissue acquisition. EUS-FNB is reported to have higher diagnostic yield while preserving specimen tissue architecture. However, data on the optimal method of EUS-FNB specimen processing is limited.

AIM

To evaluate EUS-FNB with specimen processing as histology vs EUS-FNA cytology with regards to diagnostic yield and specimen adequacy.

METHODS

All EUS-FNA and EUS-FNB performed at our institution from July 1, 2016, to January 31, 2018, were retrospectively analyzed. We collected data on demographics, EUS findings, pathology, clinical outcomes, and procedural complications in two periods, July 2016 through March 2017, and April 2017 through January 2018, with predominant use of FNB in the second data collection time period. FNA specimens were processed as cytology with cell block technique and reviewed by a cytopathologist; FNB specimens were fixed in formalin, processed for histopathologic analysis and immunohistochemical staining, and reviewed by an anatomic pathologist. Final diagnosis was based on surgical pathology when available, repeat biopsy or imaging, and length of clinical follow up.

RESULTS

One hundred six EUS-FNA and EUS-FNB procedures were performed. FNA alone was performed in 17 patients; in 56 patients, FNB alone was done; and in 33 patients, both FNA and FNB were performed. For all indications, diagnostic yield was 47.1% (8/17) in FNA alone cases, 85.7% (48/56) in FNB alone cases, and 84.8% (28/33) in cases where both FNA and FNB were performed (P = 0.0039). Specimens were adequate for pathologic evaluation in 52.9% (9/17) of FNA alone cases, in 89.3% (50/56) of FNB alone cases, and 84.8% (28/33) in cases where FNA with FNB were performed (P = 0.0049). Tissue could not be aspirated for cytology in 10.0% (5/50) of cases where FNA was done, while in 3.4% (3/89) of FNB cases, tissue could not be obtained for histology. In patients who underwent FNA with FNB, there was a statistically significant difference in both specimen adequacy (P = 0.0455) and diagnostic yield (P = 0.0455) between the FNA and FNB specimens (processed correspondingly as cytology or histology).

CONCLUSION

EUS-FNB has a higher diagnostic yield and specimen adequacy than EUS-FNA. In our experience, specimen processing as histology may have contributed to the overall increased diagnostic yield of EUS-FNB.

Keywords: Fine needle biopsy, Endoscopic ultrasound, Fine needle aspiration, Pancreatic cancer, Histology, Cytopathology

Core tip: Endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) is rapidly gaining in popularity. However, the optimal method for EUS-FNB specimen processing is not well defined, with recent studies on fine needle biopsy (FNB) varying widely in the use of histology vs cytology for FNB sample evaluation. Our data suggest that processing FNB specimens in formalin for histology, followed by evaluation by an anatomic pathologist, could contribute to overall improved diagnostic yield of EUS-FNB. An additional benefit is the decreased need for on-site cytopathology.