Adequacy evaluation of 22‐gauge needle endoscopic ultrasound‐guided tissue acquisition samples and glass slides preparation for successful comprehensive genomic profiling testing: A single institute experience

• DOI: 10.1002/deo2.70104
• Publication Date: 2025-05-10T04:40:35Z
• Authors: Tami Nagatani; Yoji Wani; Masahiro Takatani; Soichiro Fushimi; Hirofumi Inoue; Shinichiro Hori; Kyohei Kai; Hideki Yamamoto; Tetsuya Okazaki; Maki Tanioka; Hiroyuki Okada; Akira Hirasawa

AbstractObjectivesThis study aimed to evaluate the successful sequencing rate of Foundation One CDx (F1CDx) using small tissue samples obtained with a 22‐gauge needle (22G) through endoscopic ultrasound‐guided fine needle acquisition (EUS‐TA) and to propose guidelines for tissue quantity evaluation criteria and proper slide preparation in clinical practice.MethodsBetween June 2019 and April 2024, 119 samples of 22G EUS‐TA collected for F1CDx testing at Himeji Red Cross Hospital were retrospectively reviewed. Tissue adequacy was only assessed based on tumor cell percentage (≥20%). The procedure stopped when white tissue fragments reached 20 mm during macroscopic on‐site evaluation. The specimens were prepared using both ‘tissue preserving sectioning’ to retain tissue within formalin‐fixed paraffin‐embedded blocks and the ‘thin sectioning matched needle gauge and tissue length’ method with calculation to ensure minimal unstained slides for the 1 mm3 sample volume criterion. Tissue area from HE slides and sample volume were measured, and F1CDx reports were analyzed.ResultsOf 119 samples, 108 (90.8%) were suitable for F1CDx. Excluding the cases not submitted for testing, in the 45 cases where F1CDx was done using 22G EUS‐TA samples, eight (17.8%) had a sum of tissue area tissue of 25 mm2 or greater in the HE‐stained sample. However, all cases met the F1CDx 1 mm3 volume criterion by submitting > 30 unstained slides per sample. As a result, 43 of 45 cases (95.6%) were successfully analyzable.ConclusionsThe 22G EUS‐TA needle is an effective tool for providing the sufficient tissue volume required for F1CDx.