A Cone Beam CT Bronchoscopy Study of the Ultrathin Cryoprobe for Biopsy of Peripheral Lung Lesions.

Background: Compared with the standard cryoprobe, the novel ultrathin 1.1 mm cryoprobe (UTCP) has improved ergonomics, shape memory, and flexibility. The performance of UTCP has demonstrated promising results in several small trials.

Methods: In this single-center, retrospective review, we examine 200 (N=200) consecutive patients referred for cone beam CT bronchoscopic biopsy of peripheral lung lesions. We utilized an extended multimodality approach, including transbronchial needle aspirate, brush, traditional forces biopsies, UTCP biopsies, and BAL. We analyzed tool in lesion, tool touch lesion, center strike rates, and diagnostic yield. We assessed for molecular adequacy and analyzed safety.

Results: A total of 222 lesions were biopsied. We achieved a tool in lesion or tool touch lesion confirmation for all biopsy attempts (100%) and a center strike rate of 68%. AQuIRE diagnostic yield was 90%, with 60% malignant, 30% benign lung nodules, and 10% nondiagnostic. UTCP was diagnostic in 3.6 % of peripheral lung lesions biopsies when all other modalities were nondiagnostic; thus, raising our overall diagnostic yield from 86.4% to 90.1%. Our analysis demonstrates superior adequacy for molecular analysis for histologic samples (TBBX or UTCP) versus cytologic samples (FNA) ( P <0.001). Three patients (1.5%) had a pneumothorax, and 1 patient (0.5%) had moderate bleeding.

Conclusion: UTCP was diagnostic in 3.6% of peripheral lung lesions when all other modalities were nondiagnostic. In the setting of CBCT guidance, UTCP has a similar safety profile to standard biopsy tools. Future trials are warranted to assess UTCP and its impact on peripheral lung lesion biopsies.