Percutaneous Endobiliary Cryobiopsy in Biliary Obstruction: Randomised Study (BICRYOB).

DESIGN AND PURPOSE: To assess feasibility and technical outcome of endobiliary cryobiopsy compared to standard technique of endobiliary forceps biopsy in randomized study.

MATERIAL AND

METHODS

This prospective study included 22 patients with indeterminate biliary stenosis. All patients underwent percutaneous endoluminal forceps biopsy and endoluminal cryobiopsy under the fluoroscopy guidance. The order of sample collection was randomized. The technical feasibility of cryobiopsy and the rate of serious complications were analyzed. Sensitivity in detecting malignancy, sample weight, total sample area, sample area without artifacts, and sample quality (five-point Likert scale) assessed by two certified pathologists were compared between both methods.

RESULTS

No CTCAE (Common Terminology Criteria for Adverse Events) v.5 grade 3-4 complications were reported during or after the procedure, and cryobiopsy was technically feasible in all patients. Three of 22 patients were excluded from the analysis. A total of 232 samples were collected (112 forceps biopsy, 120 cryobiopsy). Cryobiopsy and forceps biopsy respectively detected carcinoma in 15/19 patients and 11/19 patients in total yielding positive diagnostic histology for malignancy in 79% and 58% (p = 0.11). Among the 17 patients ultimately diagnosed with malignancy, sensitivity for cryobiopsy and forceps biopsy was 88% and 65%, respectively and overall accuracy was 89% (17/19) or cryobiopsy and 68% (13/19) for forceps biopsy. Cryobiopsy provided significantly larger total and artifact-free sample areas (median 2.66 vs 0.84 mm2 and 1.77 vs 0.18 mm2, respectively; p < 0.001), fewer non-evaluable samples (8% vs 40%; p < 0,001), and a significantly greater median weight (7.6 vs 3.6 mg; p < 0.001). Cryobiopsy samples demonstrated markedly superior quality assessments (median Likert scale value 4 vs 2, p < 0.001; Likert > 2 in 83% vs 38%, p < 0.001).

CONCLUSION

Cryobiopsy in the biliary tract appears to be a safe and feasible technique, allowing more representative histological samples to be obtained compared with forceps biopsy.

LEVEL OF EVIDENCE: Level 1, Randomized trials.