Transbronchial Lung Cryobiopsy for Diagnosing Interstitial Lung Disease: A Retrospective Single-Center Experience

Abstract

Background: An accurate diagnosis in patients with interstitial lung diseases (ILDs) by multidisciplinary discussion (MDD) based on histopathologic information is essential for optimal treatment. Transbronchial lung cryobiopsy (TBLC) has increasingly been used as a diagnostic alternative to surgical lung biopsy. This study aimed to evaluate the appropriate methods of TBLC in patients with ILD in Korea.

Methods: A total of 27 patients who underwent TBLC were included. TBLC procedure details and clinical MDD diagnosis using TBLC histopathologic information were retrospectively analyzed.

Results: All procedures were performed under general anesthesia with the fluoroscopic guidance in the operation room using flexible bronchoscopy and endobronchial balloon blocker. The median procedure duration was less than 30 minutes, and the median number of biopsies per participant was 2. Most of the bleeding after TBLC was not severe, and the rate of pneumothorax was 25.9%. The most common histopathologic pattern was alternative (48.2%), followed by indeterminate (33.3%) and usual interstitial pneumonia (UIP)/probable UIP (18.5%). In the MDD after TBLC, the most common diagnosis was idiopathic pulmonary fibrosis (33.3%), followed by smoking-related ILD (25.9%), nonspecific interstitial pneumonia (18.6%), unclassifiable-ILD (14.8%), and others (7.4%).

Conclusion: This first single-center experience showed that TBLC using a flexible bronchoscopy and endobronchial balloon blocker with the fluoroscopic guidance under general anesthesia may be a safe and adequate diagnostic method for ILD patients in Korea. The diagnostic yield of MDD was 85.2%. Further studies are needed to evaluate the diagnostic yield and confidence of TBLC.

Keywords: Diagnosis; Interstitial Lung Disease; Multidisciplinary Discussion; Transbronchial Lung Cryobiopsy.

Fig. 1.

Histopathologic findings of TBLC specimens. (A) Probable UIP pattern. Patch fibrosis along the interlobular spectrum alternating normal alveoli in H&E stain and low power (×12.5). (B) Probable UIP pattern. Demonstration of the fibroblastic foci in alcian blue stain and high power (×200). (C) Cellular NSIP pattern. Well preserved alveolar architecture without paraseptal fibrosis in H&E stain and low power (×12.5). (D) Cellular NSIP pattern. Intra-alveolar plugs of fibrosis with moderate alveolar septal lymphoplasmacytic infiltrate in H&E stain and high power (×100). (E) Smoking-related pattern. Centriacinar fibrosis without involvement of the paraseptal area in H&E stain and low power (×12.5). (F) Smoking-related pattern. Temporally homogenous fibrosis and intra-alveolar pigmented macrophage accumulation in H&E stain and high power (×100). TBLC: transbronchial lung cryobiopsy; UIP: usual interstitial pneumonia; NSIP: nonspecific interstitial pneumonia; H&E: hematoxylin and eosin.