Heparin Wet Suction Versus Conventional Suction in Endoscopic Ultrasound-Guided Fine-Needle Biopsy for Solid Pancreatic Masses: A Multicenter Randomized Crossover Study.

BACKGROUND AND AIM: The heparin wet suction technique (HWST) may improve tissue quality in endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) by preventing blood clot formation within the needle. We compared the diagnostic performance and safety of HWST with the conventional suction technique (CST), using a novel 22-gauge FNB needle in patients with solid pancreatic masses. METHODS: In this multicenter, single-blinded, randomized crossover trial, patients with solid pancreatic masses (≥ 1 cm) were randomized 1:1 to HWST-first or CST-first. Each patient underwent one pass with each technique using the novel 22-gauge needle. The primary outcome was diagnostic yield; secondary outcomes included technical success, adverse events, and adequacy for immunohistochemistry (IHC). RESULTS: Of 174 randomized patients, 170 received both interventions and were analyzed; baseline characteristics were comparable. The diagnostic yield was 82.9% (95% confidence interval [CI], 76.6-87.9) with HWST and 83.5% (95% CI, 77.2-88.4) with CST. The paired difference was -0.6 percentage points (95% CI, -6.7 to 5.5; exact McNemar p = 1.000). The combined diagnostic yield after sequential sampling was 91.2% (95% CI, 86.0-94.6). Technical success was 100% with both techniques, and IHC adequacy was similar (HWST: 80.6% vs. CST: 78.8%). One self-limiting bleeding event occurred during CST. CONCLUSIONS: HWST showed diagnostic yield, technical success, and safety comparable to CST. Both techniques are highly effective for EUS-FNB of solid pancreatic masses. Sequential sampling may improve overall diagnostic yield, although this finding should be interpreted cautiously and requires further validation.