Concordance between sequential transbronchial lung cryobiopsy and surgical lung biopsy in patients with diffuse interstitial lung disease

Abstract

Background: Increasing evidence indicates the utility of transbronchial lung cryobiopsy (TBLC) for the diagnosis of interstitial lung disease (ILD). However, only one study has compared TBLC and surgical lung biopsy (SLB) performed on the same patients.

Methods: We identified seven patients with ILD with TBLC and SLB. We evaluated the clinical characteristics and made a pathological diagnosis based on the official ATS/ERS/JRS/ALAT clinical practice guideline of idiopathic pulmonary fibrosis with both TBLC and SLB.

Results: Six cases were diagnosed as Usual interstitial pneumonia (UIP) in both TBLC and SLB. One case was diagnosed as indeterminate for UIP with TBLC and probable UIP with SLB. Etiological diagnosis with TBLC and SLB were concordant in 2 cases of idiopathic pulmonary fibrosis (IPF) but discordant for other diagnoses. Major histological findings of UIP including dense fibrosis, peripheral distribution, and fibroblastic foci showed high concordance between TBLC and SLB, which implies that TBLC can reliably detect these features. In contrast, loose fibrosis, cellular infiltration, and airway disease showed poor concordance between the two methods.

Conclusion: Our study showed that TBLC is useful for UIP diagnosis but not for other ILD. With a multidisciplinary approach, diagnosis of IPF may be determined by TBLC, whereas ILD other than IPF may require SLB.

Keywords: Cryobiopsy; Histological findings; Interstitial lung disease; Pathology; Surgical lung biopsy.

Fig. 1

a: TBLC specimen shows mild invasion of inflammatory cells in the alveolar septum. SLB specimen reveals bone formation with myeloid tissue along the interstitium. b: Dense fibrosis and fibroblastic foci found in TBLC specimen were also seen in SLB specimen. c: Cellular IP shown in TBLC specimen were less represented in SLB specimen. d: Organizing pneumonia and PBM seen in SLB specimen were not noted in TBLC specimen

Fig. 2

a: HRCT shows linear and ground-glass opacities at the base of the lung. b: TBLC specimen indicates dense fibrosis with structural modifications in the edge of pulmonary lobule as well as fibroblast foci. c: SLB specimen reveals dense fibrosis and fibroblast foci with structural modifications spreading at the subpleural region and near the intralobular septum