Transbronchial cryobiopsy for small peripheral pulmonary lesions using endobronchial ultrasonography and an ultrathin bronchoscope

Abstract

Background: Transbronchial biopsy using an ultrathin bronchoscope (UTB) has a high diagnostic yield for peripheral pulmonary lesions (PPLs). When combined with peripheral transbronchial needle aspiration (pTBNA), it improves the diagnostic yield of "adjacent to" radial endobronchial ultrasonography (rEBUS) findings. However, pTBNA is a complicated technique, and the specimen volume is often inadequate for diagnostic and multiplex analyses. Recently, transbronchial cryobiopsy (TBCB) using a 1.1-mm cryoprobe that could be inserted into an UTB has been available. We investigated whether TBCB combined with forceps biopsy using a 1.1-mm cryoprobe with an UTB improved the diagnostic yield of "adjacent to" lesions.

Methods: The data of 66 consecutive patients who underwent TBCB and forceps biopsy using UTB (hemostasis using two-scope method) under rEBUS for small PPLs (≤30 mm) were retrospectively analyzed. The histological diagnosis rate using TBCB and forceps biopsy, TBCB alone, or forceps biopsy alone was compared between cases where the rEBUS probe was "within" and "adjacent to" lesions.

Results: The diagnosis rate using TBCB and forceps biopsy was 81.8 % for all lesions ("within" vs. "adjacent to" cases: 88.4 % vs. 69.6 %; p = 0.093). The corresponding rate using TBCB alone was 80.3 % (86.0 % vs. 69.6 %; p = 0.19), and that using forceps biopsy alone was 62.1 % (74.4 % vs. 39.1 %; p = 0.008). Bleeding leading to discontinuation of the examination occurred in four (6.1 %) patients; however, in all cases, bleeding could be controlled endoscopically.

Conclusion: Forceps biopsy with TBCB during ultrathin bronchoscopy for small PPLs improved the diagnostic yield when the lesions were adjacent to the rEBUS probe.

Keywords: Adjacent to; Cryobiopsy; Diagnosis; Peripheral lung lesions; Ultrathin bronchoscopy.