Lymphadenopathy Tissue Sampling by EUS-Guided Fine-Needle Biopsy Contributes to Meeting the Conditions for Genomic Profiling.

Background and aims: EUS-guided fine-needle biopsy (EUS-FNB) performed with a Franseen needle or Fork-tip needle enables greater tissue acquisition. However, it is unknown whether EUS-FNB could contribute to lymphadenopathy genomic profiling. The aim of this study was to determine the efficacy of EUS-FNB using a Franseen or Fork-tip needle for tissue acquisition and genomic profiling in patients with lymphadenopathy.

Patients and methods: Patients with abdominal lymphadenopathy who underwent EUS-guided fine needle aspiration (FNA)/EUS-FNB were included in this study. The amount of acquired tissue and its suitability for genomic profiling were compared between FNA and FNB. Specimen quality was evaluated by a widely used pathologic adequacy scoring system (0: insufficient; 1 to 2: cytologic; 3: limited histologic; 4 to 5: sufficient histologic). The criteria of FoundationOne CDx (F1CDx) and NCC Oncopanel (NOP) were used to assess the suitability for genomic profiling.

Results: In total, 72 patients underwent EUS-FNA, and the other 20 patients underwent EUS-FNB. The pathologic adequacy score and suitability for genomic profiling based on the criteria were significantly higher for FNB than for FNA [histologic adequacy score: 5 (4 to 5) versus 3 (0 to 5), P<0.01; F1CDx: 16.7% vs. 0%, P=0.01; NOP: 66.7% vs. 7.5%, P<0.01]. In multivariate analysis, EUS-FNB was identified as the only factor that influenced the suitability for genomic profiling based on the above-mentioned criteria (odds ratio 19.5, 95% CI: 3.74-102, P<0.01).

Conclusions: EUS-FNB performed using Franseen or Fork-tip needles may result in greater lymphadenopathy tissue acquisition and thus enhanced suitability for genomic profiling compared with EUS-FNA.