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

ABSTRACT

OBJECTIVES: 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). METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.