Utility of Endoscopic Ultrasound-Guided Biopsy for Next-Generation Sequencing of Pancreatic Exocrine Malignancies.

Objectives Endoscopic ultrasound-guided fine-needle biopsy and aspiration (EUS FNB/A) are the standard diagnostic tests for pancreatic malignancies. Oncologists increasingly use tumor genomic analysis for management. Adequacy of FNB/A tissue for next-generation sequencing (NGS) has not been evaluated. This study examined FNB/A and other biopsy types for features that might predict adequacy for NGS. Methods Seventy-six pancreatic exocrine malignancy biopsies submitted for NGS were assessed for adequacy, which was compared with other tumor/biopsy features. Results Twenty-two (29%) of 76 samples were inadequate, including 16 (30%) of 54 FNBs and 4 (57%) of 7 FNAs. Larger-gauge needles were associated with adequacy in all samples (P = 0.0047) and in FNBs (P = 0.05). Metastatic samples were more likely to be adequate for NGS compared with pancreatic samples (P = 0.0357). Percutaneous biopsies were more likely to be adequate than EUS-guided FNB/As, although this trend was not significant (P = 0.0558). Other tumor/biopsy characteristics were not associated with adequacy. Conclusions Endoscopic US FNA and FNB provided similar NGS adequacy rates. Metastatic lesions accessible by percutaneous biopsy may be preferable to EUS FNB/A of primary lesions for obtaining tissue for NGS. All biopsies, including EUS FNB, were more likely to be successful using larger-gauge needles.