Profitability of cryobiopsy in the diagnosis of diffuse interstitial lung disease

Introduction: Diffuse interstitial lung disease constitutes a very heterogeneous group of conditions that are histologically characterized by varying degrees of inflammation and fibrosis in the lung parenchyma. Cryobiopsy is a less invasive technique than surgical biopsy that could play a relevant role in the diagnosis of interstitial lung disease (ILD).

Material and methods: This is a descriptive and observational one-year study with 21 patients who were referred to our Bronchoscopic Unit for cryobiopsy after the decision of a multidisciplinary committee.

Clinical and radiological data, location of samples, complications of the technique and results of the technique were collected.

Results: Of 21 patients 57.2% were men with a mean age of 64.6 ± 9.6; 47.6% had never smoked, 66.7% had no contact with birds and 42.9% had no exposure to asbestos, 47.6% had dyspnea grade 1 mMRC (Modified Medical Research Council).

Lung function test were: FVC2284.6 ml ± 622.86 (63.5% ± 12.1%); FEV1 1923.3 ml ± 529.1 (68.6% ± 12.2%); FEV1/FVC83, 3% ± 6.1; DLCO 2.7 ± 2.1 (67.1% ± 21.9%).

The radiological patterns were: in 38.1% of cases subjective findings of nonspecific interstitial pneumonia (NSIP), in 38.1% subjective findings of usual interstitial pneumonia (UIP); and 23.8% were other types of findings.

Three samples were obtained in 62% of the cases. The most frequent locations: 38.1% in the left pyramid, 28.6% in the middle lobe, 23.8% in the right pyramid and 9.5% in other locations.

In 16 patients (76.2%) the biopsy samples were considered diagnostic: 9 cases NSIP (the most frequent finding), 6 cases of UIP and one case of poorly differentiated adenocarcinoma. In 5 of them (23.8%) the samples were considered non-diagnostic. In addition, in 12 patients (57%) there was agreement between the radiological and pathological findings.

66.7% of the cases did not suffer complications (33.3% suffered), being mild bleeding the most common in 28.6% of the cases.

Conclusions: The cryobiopsy in patients with clinical suspicion of ILD has allowed us to obtain a relevant number of pulmonary parenchyma samples with few complications, avoiding more invasive procedures. This endoscopic procedure can be a cost-effective and safe technique for the diagnosis of ILD if performed by expert personnel.