Diagnosis

CHEST Releases Guideline on Transbronchial Cryobiopsy for Diagnosing ILD

The American College of Chest Physicians (CHEST) published a guideline and expert panel report on the use of transbronchial cryobiopsy (TBC) for the diagnosis of interstitial lung diseases (ILDs). Included are 2 evidence-based graded recommendations and 4 ungraded consensus-based statements.

The guideline and report were published as the safety of surgical lung biopsy (SLB) for the diagnosis of ILD comes under fire again, as research has shown that SLB is associated with significant morbidity and mortality, according to the panel.

“Our comprehensive and systematic review of the literature suggests that TBC may be considered as an alternative to SLB, provided certain precautions are exercised, such as prophylactic use of a bronchial blocker and fluoroscopy,” the panel wrote. “These recommendations should be viewed as provisional, and contingent upon confirmation of these preliminary data and the availability of clinical pathologist experts in ILD.”

After reviewing relevant literature in MEDLINE and the Cochrane Library and assessing the quality of evidence, the expert panel developed the following evidence-based graded recommendations:

  1. TBC can be used to provide histopathologic findings for multidisciplinary discussion diagnosis among patients with suspected ILD.
  2. Biopsy of at least 2 different sites (either different segments in the same lobe or different lobes) should be performed in patients with suspected ILD undergoing TBC.

 

Because they are largely based on weak evidence, these recommendations should not be regarded as binding; clinicians should approach TBC on a case-by-case basis.

The following ungraded consensus-based statements were also made for managing patients with suspected ILD undergoing TBC:

  1. Consider biopsy with the tip of the cryoprobe located 1 cm from the pleura.
  2. Consider using fluoroscopy. 
  3. Consider performing TBC with a bronchial blocker either through an endotracheal tube or rigid bronchoscope. 
  4. Consider using a small cryoprobe (1.9 mm) vs a larger cryoprobe (2.4 mm).

 

“Evidence of the utility and safety of TBC for the diagnosis of ILD is limited but suggests TBC is safer than SLB, and its contribution to the diagnosis obtained via multidisciplinary discussion is comparable to that of SLB, although the histological diagnostic yield appears higher with SLB (approximately 80% for TBC vs 95% for SLB),” the authors concluded. “Additional research is needed to enhance knowledge regarding utility and safety of TBC, its role in the diagnostic algorithm of ILD, and the impact of technical aspects of the procedure on diagnostic yield and safety.”

—Colleen Murphy

Reference:

Maldonado F, Danoff SK, Wells AU, et al. Transbronchial cryobiopsy for the diagnosis of interstitial lung diseases: CHEST guideline and expert panel report. Chest. 2020;157(4):1030-1042. doi:10.1016/j.chest.2019.10.048