Transbronchial Lung Cryobiopsy in Diffuse Parenchymal Lung Disease: Comparison between Biopsy from 1 Segment and Biopsy from 2 Segments - Diagnostic Yield and Complications

Abstract

Background: Transbronchial lung cryobiopsy is an innovative method of obtaining samples from the parenchyma of patients with diffuse parenchymal lung diseases. However, the technique is not yet standardized, and uncertainty exists about the optimal protocol, including the number of samples, the biopsy size, and the choice of the biopsy site. Objectives: To compare the diagnostic yield and complications of cryobiopsy with different strategies adopted to sample lung tissue (number of samples, biopsy site, and sample size). Methods: We prospectively enrolled 46 patients with suspected diffuse parenchymal lung diseases for the diagnosis of which a biopsy was deemed useful. All patients underwent transbronchial lung cryobiopsy, and they were randomly assigned to group A (4 samples obtained from the same segment) or group B (2 samples obtained from one segment and 2 samples obtained from a different segment of the same lobe). Analysis of the samples was performed sequentially (from the first to the last sample), and pathologists reformulated their histopathologic diagnosis with the addition of each sample. Results: The mean diagnostic yield of the procedure combining the 2 groups and performing only the first sampling was 69%. When a second biopsy was performed as well, the mean diagnostic yield improved, but this increase was significant only when the 2 samples were obtained from 2 different segments (96%, group B). Conclusions: This study suggests that the strategy of performing 2 biopsies with a cryoprobe may be associated with an increased diagnostic yield in diffuse parenchymal lung diseases if these samples are obtained from 2 different segments within the same lobe.

Transbronchial Lung Cryobiopsy in Interstitial Lung Diseases: Best Practice

“…Although there is a debate which areas should be chosen for TBLC, it seems reasonable to target different lung areas, more affected areas, and areas with different radiological patterns. This goes along with Ravaglia et al [16] who found that taking biopsies from a different segment of the same lobe instead of biopsies from one segment rose the diagnostic yield from 69 to 96%. However, taking biopsies only from areas suspicious for pure fibrotic changes on HRCT is unlikely to provide specific histological changes and should therefore be avoided.…”

Transbronchial Cryobiopsies for the Diagnosis of Diffuse Parenchymal Lung Diseases: Expert Statement from the Cryobiopsy Working Group on Safety and Utility and a Call for Standardization of the Procedure

“…The NSIP or DIP patterns or other rarer and complicated lesions have also been identified in samples obtained by cryoprobes, although in a limited number of cases [52,53]. Thus, data on the clinical meaning of NSIP/DIP and other patterns on cryobiopsy have not been assessed yet.…”

“…Therefore, the optimal number of biopsies cannot be uniformly established, although in the majority of centers 3-5 biopsies are usually taken. However, a recent study suggested that biopsies from different segments within the same lobe are associated with a higher diagnostic yield compared to biopsies in the same segment [53]. Multiple biopsies are usually undertaken in an effort to reduce sampling error, but data on the different strategies adopted to sample lung tissue are still missing in the literature; no prospective studies have been published yet in terms of diagnostic yield and rates of complications.…”

“…Multiple biopsies are usually undertaken in an effort to reduce sampling error, but data on the different strategies adopted to sample lung tissue are still missing in the literature; no prospective studies have been published yet in terms of diagnostic yield and rates of complications. While it remains unclear whether TBCB should be obtained from 2 different lobes, prior data on interlobar heterogeneity of UIP support this practice, mainly when the CT scan does not show a clear gradient profusion of the pattern or when different patterns are present in different lobes, if optimal placement of the cryoprobe and bronchial blocker can be achieved [53].…”

Utility of Transbronchial Lung Cryobiopsy in Non-Interstitial Diseases

“…The diagnostic sensitivity of TLCB has been compared with forceps biopsy (FB), showing a better diagnostic yield in several studies [1][2][3][4] . Samples obtained by TLCB are of larger size than those of FB and lack the mechanical crush artifacts, improving the quality of the histopathology sample [5][6][7] .…”