Is diagnostic accuracy of fine needle aspiration on solid pancreatic lesions aspiration-related? A multicentre randomised trial

Background: Endoscopic ultrasound fine needle aspiration has a central role in the diagnostic algorithm of solid pancreatic masses. Data comparing the fine needle aspiration performed with different aspiration volume and without aspiration are lacking. We compared endoscopic ultrasound fine needle aspiration performed with the 22 gauge needle with different aspiration volumes (10, 20 and 0 ml), for adequacy, diagnostic accuracy and complications.

Methods: Prospective clinical study at four referral centres. Endoscopic ultrasound fine needle aspiration was performed with a 22G needle with both volume aspiration (10 and 20 cc) and without syringe, in randomly assigned sequence. The cyto-pathologist was blinded as to which aspiration was used for each specimen.

Results: 100 patients met the inclusion criteria, 88 completed the study. The masses had a mean size of 32.21±11.24 mm. Sample adequacy evaluated on site was 87.5% with 20 ml aspiration vs. 76.1% with 10 ml (p=0.051), and 45.4% without aspiration (20 ml vs. 0 ml p<0.001; 10 ml vs. 0 ml p<0.001). The diagnostic accuracy was significantly better with 20 ml than with 10 ml and 0 ml (86.2% vs. 69.0% vs. 49.4% p<0.001).

Conclusions: A significantly higher adequacy and accuracy were observed with the 20 ml aspiration puncture, therefore performing all passes with this volume aspiration may improve the diagnostic power of fine needle aspiration.