Transbronchial Cryobiopsies: Evidence Moving at Glacial Speed?

Abstract

SESSION TITLE: Interventional Pulmonology Posters IISESSION TYPE: Original Investigation PosterPRESENTED ON: Wednesday, October 28, 2015 at 01:30 PM - 02:30 PMPURPOSE: We reviewed our experience at a quaternary-care academic medical center with transbronchial cryobiopsies to highlight varying methodology, potential complications, and question the superiority of this format over standard transbronchial forceps biopsies.METHODS: We performed a retrospective review of our experience in obtaining transbronchial cryobiopsies in 25 patients. All procedures were performed under general anesthesia with a therapeutic flexible bronchoscope (Olympus, BF-1T180 or BF-1T160), via laryngeal mask airway (LMA) or endotracheal tube. Both 1.9 mm and 2.4 mm cryoprobes (Erbokryo CA) were used. Freeze times (2-4 seconds) and probe position in the airway varied, depending on the proceduralist's assessment of the parenchymal abnormalities noted on imaging.RESULTS: Twenty-five patients underwent transbronchial cryobiopsies. In 12 of these cases, standard forceps transbronchial biopsies were also performed, and were sent separately from cryobiopsy specimens in 8 of the 12 cases. Of the 8 cases in which specimens were sent separately, the final diagnosis on transbronchial cryobiopsy was identical to that obtained with transbronchial forceps biopsies. One case of non-specific interstitial pneumonia (NSIP) was diagnosed on cryobiopsy alone. There were no other diagnoses of NSIP, usual interstitial pneumonia (UIP), or hypersensitivity pneumonitis (HP). Pneumothorax occurred in 2 patients. Significant bleeding was reported in 4 patients, including one massive bleed, prompting a voluntary moratorium on transbronchial cryobiopsies at our institution.CONCLUSIONS: Methodology studies demonstrating best practices in utilizing transbronchial cryobiopsy technology are lacking, and potential complications demand additional study in this area.CLINICAL IMPLICATIONS: The small size of transbronchial biopsies obtained with standard flexible forceps has long been considered inadequate for the diagnosis of interstitial lung disease. Prior studies have suggested that transbronchial cryobiopsies obtain larger parenchymal tissue samples with preserved architecture capable of diagnosing interstitial lung disease, or, in cases of malignancy, to ensure adequate tissue for molecular studies. Our experience highlights the need for evidence-based methodology in obtaining parenchymal cryobiopsies. Factors that currently vary widely include probe size, probe airway position, freeze time, and airway management. Direct, randomized comparison to standard forceps transbronchial biopsies in human subjects has yet to be investigated.DISCLOSURE: The following authors have nothing to disclose: Jamie Bessich, Laura Frye, Edmund Moon, Anthony Lanfranco, Andrew Haas, Anil Vachani, Daniel StermanNo Product/Research Disclosure Information SESSION TITLE: Interventional Pulmonology Posters II SESSION TYPE: Original Investigation Poster PRESENTED ON: Wednesday, October 28, 2015 at 01:30 PM - 02:30 PM PURPOSE: We reviewed our experience at a quaternary-care academic medical center with transbronchial cryobiopsies to highlight varying methodology, potential complications, and question the superiority of this format over standard transbronchial forceps biopsies. METHODS: We performed a retrospective review of our experience in obtaining transbronchial cryobiopsies in 25 patients. All procedures were performed under general anesthesia with a therapeutic flexible bronchoscope (Olympus, BF-1T180 or BF-1T160), via laryngeal mask airway (LMA) or endotracheal tube. Both 1.9 mm and 2.4 mm cryoprobes (Erbokryo CA) were used. Freeze times (2-4 seconds) and probe position in the airway varied, depending on the proceduralist's assessment of the parenchymal abnormalities noted on imaging. RESULTS: Twenty-five patients underwent transbronchial cryobiopsies. In 12 of these cases, standard forceps transbronchial biopsies were also performed, and were sent separately from cryobiopsy specimens in 8 of the 12 cases. Of the 8 cases in which specimens were sent separately, the final diagnosis on transbronchial cryobiopsy was identical to that obtained with transbronchial forceps biopsies. One case of non-specific interstitial pneumonia (NSIP) was diagnosed on cryobiopsy alone. There were no other diagnoses of NSIP, usual interstitial pneumonia (UIP), or hypersensitivity pneumonitis (HP). Pneumothorax occurred in 2 patients. Significant bleeding was reported in 4 patients, including one massive bleed, prompting a voluntary moratorium on transbronchial cryobiopsies at our institution. CONCLUSIONS: Methodology studies demonstrating best practices in utilizing transbronchial cryobiopsy technology are lacking, and potential complications demand additional study in this area. CLINICAL IMPLICATIONS: The small size of transbronchial biopsies obtained with standard flexible forceps has long been considered inadequate for the diagnosis of interstitial lung disease. Prior studies have suggested that transbronchial cryobiopsies obtain larger parenchymal tissue samples with preserved architecture capable of diagnosing interstitial lung disease, or, in cases of malignancy, to ensure adequate tissue for molecular studies. Our experience highlights the need for evidence-based methodology in obtaining parenchymal cryobiopsies. Factors that currently vary widely include probe size, probe airway position, freeze time, and airway management. Direct, randomized comparison to standard forceps transbronchial biopsies in human subjects has yet to be investigated. DISCLOSURE: The following authors have nothing to disclose: Jamie Bessich, Laura Frye, Edmund Moon, Anthony Lanfranco, Andrew Haas, Anil Vachani, Daniel Sterman No Product/Research Disclosure Information