The Application Value and Safety of Ultrafine Bronchoscopy Combined with Frozen Lung Biopsy in the Diagnosis of Peripheral Pulmonary Nodules

Accurate diagnosis of peripheral pulmonary nodules (PPNS) remains challenging due to their small size and location. Conventional transbronchial forceps biopsy often yields suboptimal tissue samples. Cryobiopsy has emerged as a promising technique to improve diagnostic accuracy. The objective of this study is to evaluate the diagnostic yield, specimen quality, and safety profile of ultrathin bronchoscopy-guided transbronchial cryobiopsy in patients with PPNS, and to compare it with conventional forceps biopsy. In this retrospective, observational study conducted from January 2023 to December 2024 at the department of pulmonary medicine, 60 adult patients with CT-confirmed PPNS (8-30 mm) underwent bronchoscopy evaluation using ultrathin bronchoscopy, radial endobronchial ultrasound (R-EBUS), and virtual navigation. Cryobiopsies were obtained using a 1.1 mm cryoprobe, with forceps biopsy performed in 75% of patients for comparison. The primary outcome was diagnostic yield; secondary outcomes included complication rates, specimen size, tissue quality, and procedural metrics. A definitive histopathological diagnosis was achieved in 48 of 60 cases, yielding an overall diagnostic rate of 80%. Cryobiopsy demonstrated a significantly higher diagnostic yield (85%) compared to forceps biopsy (62%, p < 0.05). Cryobiopsy specimens were significantly larger (5.2 ± 1.1 mm vs 2.1 ± 0.7 mm) with p < 0.05 and had less crush artifact (92% vs 58%). Malignancy was diagnosed in 34 patients (56.7%), with adenocarcinoma being the most common. Complication rates were low; pneumothorax occurred in 2 cases (3.3%) and moderate bleeding in 5 cases (8.3%), all managed conservatively. Transbronchial cryobiopsy is a safe and superior diagnostic modality for evaluating PPNS, offering higher diagnostic yield and better specimen quality than forceps biopsy. It should be considered an effective, minimally invasive option for tissue acquisition in patients with indeterminate pulmonary nodules. However, the study's single-center design and limited sample size may restrict generalizability.