Diagnosing Interstitial Lung Disease: A Comparison of 3 Biopsy Methods

An assessment of biopsy methods for diagnosing interstitial lung disease found good agreement between transbronchial lung cryobiopsy (TBLC), an emerging, less-invasive biopsy method, and surgical lung biopsy. A report on this assessment was recently published by the journal Respiration.

The comparative, prospective clinical trial, conducted at 4 centers in the US, included 16 participants referred to thoracic surgery by a pulmonologist to undergo video-assisted thoracoscopic surgical lung biopsy (VATS SLB) for suspected interstitial lung disease (ILD). All participants agreed to undergo sequential forceps transbronchial lung biopsy (TBLB) and TBLC performed by an experienced interventional pulmonologist followed immediately by a VATS SLB performed by an experienced thoracic surgeon. Cases were then reviewed by a pathologist who was blinded to the source, had no relevant clinical history, and did not see specimens in sequence. All findings were then discussed at a multidisciplinary conference where the final diagnosis was made regarding ILD.

When the diagnostic methods were compared, raw agreement between TBLC and the VATS SLB for the multidisciplinary discussion final diagnosis was 68.75% with a Cohen’s kappa of 0.6. TBLC was associated with mild bleeding (grade 1 bleeding requiring suction to clear) in 56.2% of patients. Notably, raw agreement between forceps TBLB and the VATS SLB for the multidisciplinary discussion final diagnosis was 18.75% with a Cohen’s kappa of 0.08. “As expected, TBLB performed much worse than TBLC and SLB confirming its relative ineffectiveness as a biopsy method for ILD,” the investigators noted.

The study authors concluded that “Our study adds to the evidence that TBLC can be a valuable option in the evaluation of patients with ILD where determination of a specific ILD type is needed and cannot be obtained with clinical and imaging data only.” They added, “Clinicians should weigh the benefits and risks of each biopsy method and customize the approach to their particular patients with ILD.”

Reference

Wahidi MM, Argento AC, Mahmood K, et al. Comparison of forceps, cryoprobe, and thoracoscopic lung biopsy for the diagnosis of interstitial lung disease – the CHILL Study. Respiration. Published online November 16, 2021. doi:10.1159/000519674