P3713 - Optimizing Next-Generation Sequencing Analysis of Pancreatic Cancer Using Endoscopic Ultrasound-Guided Fine-Needle Biopsy: A Tertiary Care Experience

Vaia Florou, MD¹, Daryl Ramai, MD, MSc², John Morris, MD¹, Christopher Ko, MD¹, Kathryn Byrne, MD¹, Douglas G. Adler, MD³, Jarrod Smith, MD¹, Chris Nevala-Plagemann,, MD¹, Kristin Barber, MD¹, Lauren Olson, MD¹, Heloisa Soares, MD¹, Ignacio Garrido-Laguna, MD^1
1University of Utah Health, Salt Lake City, UT; ²University of Utah, Salt Lake City, UT; ³Center for Advanced Therapeutic (CATE), Centura Health, Porter Adventist Hospital, Peak Gastroenterology, Denver, CO

Introduction: Endoscopic fine needle biopsy (EUS-FNB) is an effective tissue sampling modality for diagnosing pancreatic cancer. Genomic sequencing is becoming essential with the emerging targeted therapies in pancreatic cancer. However, the feasibility of commercial comprehensive next-generation sequencing on tissue obtained from EUS-FNB is unknown. We aimed to examine the success rate of genomic sequencing utilizing tissue from EUS-FNB and correlate it with procedural characteristics.

Methods: We retrospectively reviewed a consecutive cohort of patients who underwent a diagnostic EUS-FNB during the workup of a pancreatic mass, over five years, at our institution. Genomic results, patient demographics, tumor characteristics, and technical aspects of the EUS-FNB were reviewed. Needle passes were grouped into three categories, namely, 1-2 passes, 3 passes, and 4 or more passes. Tumor location was grouped as distal (involving the body or tail) or proximal (head, neck, or uncinate).

Results: A total of 396 patients underwent endoscopic ultrasound with pancreatic mass biopsy as part of the routine diagnostic workup. Tumor sequencing from the pancreatic EUS-FNB was requested from 101 patient samples. The remaining samples had no sequencing performed. Of the 101 patients, sequencing was successful in 88 samples (87%). Tumor purity information was available in 71 samples; the average purity was 32% (range 20-90%). Genomic sequencing was unsuccessful in the remaining 13 samples (13%) due to inadequate tissue. The cancer stage distribution was the following: I (9%), II (10%), III (14%), and IV (67%). The median number of needle passes to obtain sufficient tissue for completion of sequencing was 3 (range, 1-5). When compared to 1-2 needle passes, additional needle passes were not superior in yielding successful tumor sequencing (3 passes OR 1.2, 95% 0.36 – 4.3, P=0.730; 4-5 passes OR 3.70; 0.42 – 32.28, P=0.237). Compared to 22-gauge needles, 25-gauge needles did not yield superior tissue samples (OR 2.20; 95% 0.26 – 18.38; P=0.468). On multivariable logistic regression (table 1), distal tumor location was more likely to yield successful genomic sampling (OR 6.08; 95% CI 1.16 – 31.96; P=0.033).

Discussion: Comprehensive genomic sequencing of all stages of pancreatic cancer can be achieved using EUS-FNB. Tumor location was associated with higher success of genomic sequencing. Additional FNB needle passes, and needle gauge was not associated with increased yield.


Disclosures:


Vaia Florou, MD¹, Daryl Ramai, MD, MSc², John Morris, MD¹, Christopher Ko, MD¹, Kathryn Byrne, MD¹, Douglas G. Adler, MD³, Jarrod Smith, MD¹, Chris Nevala-Plagemann,, MD¹, Kristin Barber, MD¹, Lauren Olson, MD¹, Heloisa Soares, MD¹, Ignacio Garrido-Laguna, MD¹. P3713 - Optimizing Next-Generation Sequencing Analysis of Pancreatic Cancer Using Endoscopic Ultrasound-Guided Fine-Needle Biopsy: A Tertiary Care Experience, ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.