Agreement high between cryobiopsy, surgical biopsy for ILD diagnosis

New data demonstrating good agreement between transbronchial lung cryobiopsy and surgical lung biopsy support the use of the technology as an alternative to surgical biopsy for patients requiring lung tissue for a diagnosis of interstitial lung disease.

The COLDICE study, which was presented at the European Respiratory Society International Congress and simultaneously published in The Lancet Respiratory Medicine, was a prospective, multicenter study conducted at nine Australian tertiary hospitals designed to investigate the diagnostic agreement between transbronchial lung cryobiopsy and surgical lung biopsy.

“Compared to the reference standard, surgical lung biopsy, cryobiopsy offered potential advantages, including less risk to the patient and lower health care resource utilization. We recognized that data on the accuracy of cryobiopsy were lacking, and so we decided to conduct the COLDICE trial to address this issue,” Lauren K. Troy, PhD, from the Royal Prince Alfred Hospital in Sydney, wrote in an email to Healio Pulmonology. “In the study, we sampled both cryobiopsies and surgical lung biopsies from the same patients and assessed their agreement for the diagnosis of ILD.”

Patients with low-confidence diagnosis or unclassifiable ILD underwent sequential transbronchial lung cryobiopsy and surgical lung biopsy under a single general anesthetic. Each tissue sample was assigned a number from 1 to 130 and encoded samples were evaluated by masked pathologists. During subsequent multidisciplinary discussion, deidentified cases were discussed twice with cryobiopsy or surgical biopsy along with other data.

Coprimary endpoints included agreement of histopathological features in cryobiopsy and surgical biopsy for patterns of definite or probable usual interstitial pneumonia, indeterminate for usual interstitial pneumonia and alternative diagnosis, and agreement of consensus clinical diagnosis using cryobiopsy and surgical biopsy at the multidisciplinary discussion.

High agreement

Transbronchial lung cryobiopsy and surgical lung biopsy samples were taken from two separate ipsilateral lobes in the 65 patients (mean age, 66.1 years; 48% men) with fibrotic ILD enrolled in the study. Upon analysis, histopathological agreement between the two techniques was 70.8% and diagnostic agreement at multidisciplinary discussion was 76.9%.

Additionally, clinicians had high confidence or definite final multidisciplinary discussion diagnoses in 60% of cases with transbronchial lung cryobiopsy and 74% of cases with surgical lung biopsy (P = .09). In transbronchial lung cryobiopsy cases with high or definite diagnostic confidence at multidisciplinary discussion, there was 95% concordance with surgical lung biopsy diagnoses at multidisciplinary discussion. For the 26 cases with low confidence or unclassifiable transbronchial lung cryobiopsy diagnoses, 23% were reclassified with surgical lung biopsy to alternative high confidence or definite diagnoses at multidisciplinary discussion.

“The surgical biopsy only added additional diagnostic information for 1 in 10 patients. These results were somewhat surprising, given that the cryobiopsy is many magnitudes smaller in size compared with the surgical biopsy,” Troy said.

The study was not designed to compare safety of the procedures, but the researchers noted that 22% of patients experienced mild to moderate airway bleeding due to transbronchial lung cryobiopsy and 2% of patients died at 90 days.

Potential for transbronchial lung cryobiopsy

In light of these findings, Troy noted that transbronchial lung cryobiopsy likely has a place in clinical practice.

“The study shows that the cryobiopsy has good agreement with the surgical biopsy and thus should be considered as a reliable first-line diagnostic test for patients with ILD. Specifically, it should be considered for those patients requiring a biopsy to clarify their specific disease,” she said. “The study also highlights the importance of multidisciplinary discussion to aid with decision-making and confident diagnosis. To ensure appropriate patient selection and safety, we advocate for the procedure to be performed in expert centers with sufficient procedural training and affiliated ILD multidisciplinary teams.”

In a linked comment, Christopher J. Ryerson, MD, MAS, from the department of medicine at the University of British Columbia and Centre for Heart Lung Innovation at St. Paul’s Hospital, and Kerri A. Johannson, MD, MPH, from the department of medicine at the University of Calgary, noted that the COLDICE findings should be viewed in the context of other data showing poor accuracy or variable risk of complications with transbronchial lung cryobiopsy.

“All data considered, there appears to be a role for transbronchial lung cryobiopsy, but ILD programs considering implementation should select patients thoughtfully and adhere to standardized procedural approaches,” they wrote. “It is also essential to remember that both transbronchial lung cryobiopsy and surgical lung biopsy are imperfect tests and there remains a clear need for better diagnostics such as molecular classifiers that can remove the reliance on histopathological pattern.” – by Melissa Foster

References:

Troy L, et al. ALERT: Abstracts Leading to Evolution in Respiratory Medicine Trials: Interstitial lung disease and pulmonary hypertension. Presented at: European Respiratory Society International Congress; Sept. 28-Oct. 2, 2019; Madrid.

Troy LK, et al. Lancet Respir Med. 2019;doi:10.1016/S2213-2600(19)30342-X.

Ryerson CJ, et al. Lancet Respir Med. 2019;doi:10.1016/S2213-2600(19)30344-3.

For more information:

Lauren K. Troy, PhD, can be reached at ltroy@med.usyd.edu.au.

Disclosures: This study was supported by educational grants and/or in-kind support from Cook Medical, Erbe Elektromedizin GmbH, Medtronic, Olympus, Rymed and Zeiss. Troy reports she has received grants from Erbe Elektromedizin, Medtronic, Olympus and Rymed; nonfinancial support from Cook Medical, Karl-Storz and Zeiss; grants and personal fees from Boehringer Ingelheim and Roche; and personal fees from Menarini. Please see the study for all other authors’ relevant financial disclosures. Ryerson reports he has received honoraria and grants from Boehringer Ingelheim and F. Hoffmann-La Roche. Johannson reports she has received honoraria from Boehringer Ingelheim, Hoffmann-La Roche, Theravance and Blade Therapeutics, and grants from The Chest Foundation and UCB Biopharma SPRL.