A prospective randomized study comparing 25-G and 22-G needles of a new platform for endoscopic ultrasound-guided fine needle aspiration of solid masses.

Background: A new needle platform for endoscopic ultrasound-guided fine-needle aspiration biopsy has been developed that allows interchangeability of all needle sizes.

Aims: To prospectively compare the efficacy of the new 25-G needles and 22-G needles for obtaining an adequate aspirate of solid masses.

Methods: Randomized controlled trial of 144 patients referred for endoscopic ultrasound-guided fine-needle aspiration of solid pancreatic masses, intraparietal tumours, or lymph-nodes, randomized to the 25-G or 22-G needle arms.

Results: An adequate specimen was obtained from 74.3% of cases. The sample tended to be more adequate in the 25-G compared to the 22-G group (81% vs. 68%; p=0.09). Crossover was required in 14 (19%) and 12 (17%) cases in the 22-G and in the 25-G groups, respectively (p=0.7). The overall rate of adequacy improved from 74% before crossover to 90% after crossover (p<0.01). When comparing the two groups after crossover, the rate of obtaining adequate samples was significantly higher in the 25-G arm than in the 22-G arm (95.8% vs. 86.1%; p=0.03).

Conclusions: The 25-G needle was superior to the 22-G needle for endoscopic ultrasound-guided fine-needle aspiration biopsy. The adequacy and diagnostic accuracy improved after crossover, reaching 90%.