AT THE ERS CONGRESS 2016

LONDON (FRONTLINE MEDICAL NEWS) – The vast majority of surgical lung biopsies currently used to diagnose interstitial lung diseases (ILDs) could be avoided, suggests research presented at the annual congress of the European Respiratory Society.

During an oral presentation, Benjamin Bondue, MD, of Hopital Erasme, Brussels, presented the preliminary results of a Belgian prospective study evaluating the role of transbronchial lung cryobiopsies in 24 patients with undefined ILD treated at three participating centers.

Cryobiopsies were found to have a diagnostic yield of 79%, meaning that patients might be able to avoid undergoing a more invasive surgical removal of tissue in many cases. Compared with surgical biopsy, cryobiopsies offered the potential advantage of lower morbidity and shorter hospitalization time, Dr. Bondue said. He reported that patients needed to stay in hospital just 1.2 days after the procedure in the study.

“Our data also show that there is some benefit of surgical lung biopsy after cryobiopsy if we identify an NSIP [nonspecific interstitial pneumonia] pattern or idiopathic conditions, or if we cannot obtain a clear pathological diagnosis,” he reported. Acknowledging the study was small and conducted in a single center, he said the use of cryobiopsies following surgical biopsy might be worth further study.

Transbronchial lung cryobiopsy is a relatively new technique that uses a cryoprobe inserted down through a bronchoscope about 1-2 cm from the thoracic wall. Once in place, the probe is cooled for between 3 and 6 seconds, lung tissue freezes to the probe, and the probe and bronchoscope are removed together. This method allows for larger samples of tissue to be taken than does traditional transbronchial biopsy, which involves using large forceps to obtain tissue samples ( Respirology. 2014;19:645-54 ).

In the Belgian study, Dr. Bondue noted that a Fogarty balloon was used to control any bleeding and that four transbronchial lung cryobiopsies were obtained from two different segments of the same lobe of a patient’s lungs. All biopsies were then analyzed by an expert pathologist in ILDs, and reviewed by two other expert pathologists when needed. The mean sample size obtained was 16 mm2.

The patients included in the study had undergone chest X-ray and had inconclusive findings in the majority (84%) of cases. They then had the option to undergo cryobiopsy or surgical lung biopsy, with the latter performed following discussion among a multidisciplinary team’s members.

Following cryobiopsy, 16 of the 24 patients – who were a mean age of 62 years, and over half of whom were past (56%) or current (12%) smokers – were diagnosed with a specific pattern of ILD not due to NSIP. Of the 16 cases, 6 were due to hypersensitive pneumonitis, 4 were due to interstitial pulmonary fibrosis, and 2 were due to sarcoidosis. The other four cases included patients with one of the following conditions: adenocarcinoma, desquamative interstitial pneumonia, eosinophilic pneumonia, and amyloidosis.

Six of the 24 cases were defined as NSIP, with 2 reclassified as definite and 1 as probable hypersensitive pneumonitis, after discussion within the multidisciplinary team.

Five patients – three who had been diagnosed with NSIP and two who had been given no pathological diagnosis after cryobiopsy – underwent surgical lung biopsy. Of these, following the surgical biopsies, only one patient was considered to have NSIP and the other four were eventually diagnosed with interstitial pulmonary fibrosis.

In terms of safety, five patients experienced pneumothorax, two patients required chest drainage, two needed simple aspiration and one underwent observation. In the majority of cases, patients experienced mild bleeding, with only one patient having experienced severe bleeding. During this study, none of the participants experienced significant chest pain, acute exacerbations, or infections, and none of them died.

Dr. Bondue has received research grants and fees for consulting from Boehringer Ingelheim and Roche.

Ads