Endosonography-guided fine-needle aspiration biopsy: diagnostic accuracy and complication assessment.

Endosonography-guided fine-needle aspiration biopsy (EUS-FNA) permits cytological confirmation of EUS findings. A multicenter prospective evaluation of EUS-FNA for primary diagnosis, staging, and/or follow-up purposes was undertaken. EUS-FNA was performed in 457 patients with 554 lesions. Clinical (n = 218) or histopathologic (n = 256) confirmation was available in 192 lymph nodes, 145 extraluminal masses, 115 gastrointestinal wall lesions, and 22 cystic lesions. EUS-FNA sensitivity, specificity, and accuracy was 92%, 93%, and 92% for lymph nodes, 88%, 95%, and 90% for extraluminal masses, and 61%, 79%, and 67% for gastrointestinal wall lesions, respectively. The sensitivity and accuracy for lymph nodes and extraluminal masses was superior to that for gastrointestinal wall lesions. When EUS-FNA was compared with EUS size criteria in lymph node evaluation, specificity (93% vs. 24%) and accuracy (92% vs. 69%) were superior, whereas sensitivity (92% vs. 86%) was similar. The accuracy of EUS-FNA in patients with previously failed biopsy procedures was 81% (73 of 90). Five nonfatal complications occurred for a rate of 0.5% (95% confidence interval, 0.1%-0.8%) in solid lesions vs. 14% (95% confidence interval, 6%-21%) in cystic lesions. EUS-FNA accurately and safely evaluates solid peri-intestinal lesions and improves lymph node staging accuracy.