Diagnostic Yield of Ultrasound-Guided Vacuum Fine-Needle Aspiration Biopsy Using Small-Diameter Needles in Tumor Lesions of the Liver, Pancreas, and Lymph Nodes: a Clinical-Experimental Study.

Purpose : To evaluate the diagnostic informativeness and clinical efficiency of vacuum-assisted fine-needle aspiration biopsy (v-FNA) under ultrasound guidance in liver, pancreatic, and lymph node tumors, and to assess the feasibility of using small-diameter needles (20–25G) without compromising diagnostic accuracy. Materials and Methods : The study included 62 patients (32 men, 30 women) with suspected neoplastic lesions of the liver, pancreas, and lymph nodes. A total of 76 biopsies were performed under real-time ultrasound guidance using Chiba needles (20G, 22G, and 25G). Vacuum aspiration was performed under a constant negative pressure of −0.8 bar. Cytological preparations were stained by the May–Grünwald–Giemsa method and evaluated according to the WHO Classification of Tumours (5th Edition, 2022). Results : The overall rate of diagnostically adequate smears increased from 72.3 % with FNA to 89.5 % with v-FNA. The greatest improvement was observed in pancreatic and lymph node biopsies. Small-diameter needles (25G) yielded sufficient cellular material for reliable cytological diagnosis with minimal trauma. Concordance between cytological and histological diagnoses reached 85.7 %. Conclusions : Vacuum-assisted fine-needle aspiration biopsy under ultrasound control is a reliable, safe, and reproducible method of cytological diagnosis for intra-abdominal tumors. The use of controlled negative pressure allows for smaller needles without loss of diagnostic yield, expanding clinical applicability and improving the overall quality of cytological evaluation.