A novel flexible cryoprobe for EUS-guided pancreatic biopsies

Background: EUS-guided FNA (EUS-FNA) is an established technique for the cytologic diagnosis of pancreatic disease. Attempts to obtain adequate histologic specimens have yielded variable and mostly insufficient results.

Objective: To evaluate the safety, feasibility, and quality of histologic biopsy specimens obtained by using a new cryobiopsy probe and to compare them with standard EUS-FNA and (laparoscopic) trucut biopsy specimens of pancreatic tissue.

Design: Animal non-survival study.

Intervention: Eighty-four pancreatic biopsy specimens (12 per group) were obtained in 4 anesthetized pigs by using one of the following the 18-gauge flexible cryoprobe; a conventional, 19-gauge, EUS-FNA needle; or a rigid, trucut biopsy device (18 gauge). The latter, used in laparoscopic surgery, was considered as the criterion standard for obtaining histology specimens.

Main outcome measurements: Specimens were evaluated for artifacts and specimen quality by a blinded pathologist who used a 7-point Likert scale to assess histologic adequacy. Biopsy size and bleeding time after biopsy also were recorded.

Results: The new cryoprobe was equivalent to the rigid, trucut needle and superior (P < .001) to the conventional 19-gauge FNA needles with respect to artifacts, quality of the specimen, biopsy specimen size, and bleeding.

Limitations: Animal model.

Conclusion: EUS-guided cryobiopsy was associated with better specimen quality for histologic analysis and a shorter bleeding time compared with a conventional 19-gauge FNA needle in the animal model. It is a promising new technique for histologic examination of pancreatic tissue.