Abstract
BACKGROUND: Shape-sensing robotic-assisted bronchoscopy (ssRAB) combined with intraoperative imaging optimizes tool-lesion relationship during the sampling of focal pulmonary lesions. Nevertheless, confirmation of tool-in-lesion status is not equivalent to diagnostic sampling. This gap may be bridged by the addition of transbronchial cryobiopsy (TBCB) to traditional transbronchial needle aspiration (TBNA) and forceps biopsy (TBFB); however, the performance of TBCB, specifically with the 1.7-mm cryoprobe, has raised significant safety concerns. OBJECTIVE: Evaluate the safety of TBCB using the 1.7-mm cryoprobe, added into ssRAB-guided TBNA and TBFB, and performed via a protocolized approach in a cancer center patient population undergoing lung biopsy for focal parenchymal pulmonary lesions. Secondary endpoints included diagnostic yield, accuracy, and TBFB vs. TBCB tissue quality measures. METHODS: This prospective, single center, single arm study, enrolled patients referred for sampling of focal pulmonary parenchymal lesions. All procedures were performed with image-guided ssRAB with prophylactic balloon occlusion. The primary endpoint was a safety composite of grade ≥ 2 bleeding, grade ≥ 2 pneumothorax, or other biopsy-related grade ≥ 3 complication. Secondary endpoints included conservative diagnostic yield, diagnostic accuracy for malignancy, and biopsy specimen quality measures. RESULTS: Fifty-one participants were enrolled and underwent image-guided ssRAB. The primary severe adverse event rate was 0% (95% CI 0.0-7.9). The conservative diagnostic yield was 92% and the diagnostic accuracy for malignancy was 90%. TBCB was superior to forceps biopsy in measures of total specimen dimensions, diagnostic tissue area, and degree of crush artifact (P < 0.001 for all comparisons). CONCLUSION: In cancer patients with localized parenchymal lung lesions, the incorporation of a rigorous safety protocol into image-guided ssRAB allows for the safe acquisition of high-quality peripheral lung TBCB specimen, utilizing the 1.7-mm cryoprobe. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT04548830.