Abstract
There is a paucity of evidence on the comparison between endoscopic ultrasound (EUS) fine-needle biopsy (FNB) and fine-needle aspiration (FNA) for lymph node (LNs) sampling. The aim of this study was to compare these two approaches in a multicenter series of patients with abdominal tumors. Out of 502 patients undergoing EUS sampling, two groups following propensity score matching were compared: 105 undergoing EUS-FNB and 105 undergoing EUS-FNA. The primary outcome was diagnostic accuracy. Secondary outcomes were diagnostic sensitivity, specificity, sample adequacy, optimal histological core procurement, number of passes, and adverse events. Median age was 64.6 years, and most patients were male in both groups. Final diagnosis was LN metastasis (mainly from colorectal cancer) in 70.4% of patients in the EUS-FNB group and 66.6% in the EUS-FNA group (p = 0.22). Diagnostic accuracy was significantly higher in the EUS-FNB group as compared to the EUS-FNA group (87.62% versus 75.24%, p = 0.02). EUS-FNB outperformed EUS-FNA also in terms of diagnostic sensitivity (84.71% vs. 70.11%; p = 0.01), whereas specificity was 100% in both groups (p = 0.6). Sample adequacy analysis showed a non-significant trend in favor of EUS-FNB (96.1% versus 89.5%, p = 0.06) whereas the histological core procurement rate was significantly higher with EUS-FNB (94.2% versus 51.4%; p < 0.001). No procedure-related adverse events were observed. These findings show that EUS-FNB is superior to EUS-FNA in tissue sampling of abdominal LNs.