Comparison of 19G FNA Versus 22G FNB Needles for Endoscopic Ultrasound-Guided Fine-Needle Sampling of Subepithelial Tumors: Is Bigger Better?

Abstract

To compare the diagnostic efficiency of 19G fine-needle aspiration (FNA) and 22G fine-needle biopsy (FNB) in endoscopic ultrasound (EUS)-guided sampling for subepithelial tumors (SETs). The data of patients with SETs who underwent 19G FNA or 22G FNB were reviewed retrospectively in two tertiary hospitals. Tissue cores were assessed by macroscopic on-site evaluation (MOSE). Cytological or histological diagnosis were classified as definite, suspect, or no diagnosis. Seventy five patients (mean age: 55 years, 44 males) underwent 19G EUS-FNA (31) or 22G EUS-FNB (44). The overall diagnostic yield was 82.7%. The rate of definite cytological diagnoses was 9.7% (3/31) in 19G and 13.6% (6/44) in 22G group (x2 = 1.520, P = .468). In terms of MOSE, 19G needle, requiring only two punctures, achieved a higher good tissue core rate than 22G group (100.0% [31/31] versus 84.1% [37/44], x2 = 5.440, P = .020]). For histological diagnosis, the 19G group achieved higher definite rate than the 22G group, 93.6% (29/31) versus 65.9% (29/44) (x2 = 7.957, P = .019) on the first puncture, 90.3% (28/31) versus 63.6% (28/44) (x2 = 7.139, P = .028) on the second puncture, 96.8% (30/31) versus 70.5% (31/44) (x2 = 7.319, P = .026) on both the first and second punctures, and 96.8% (30/31) versus 72.7% (32/44) (x2 = 7.538, P = .023) on all three punctures. The 19G EUS-FNA requires only two punctures to achieve better tissue core quality by MOSE and yields a higher rate of histological diagnosis than 22G ProCore needle for SETs. The bigger 19G FNA needle seems to play an important role in the evaluation of SETs.