Lung cryobiopsies: a paradigm shift in diagnostic bronchoscopy?

Abstract

In 1963, the first bronchoscopic lung biopsy was performed. Less than 10 years later, the technique of transbronchial lung biopsy using a flexible bronchoscope was introduced into clinical practice, significantly reducing the rate of major complications and the rate of surgical lung biopsies in patients with diffuse parenchymal lung diseases. The diagnostic yield of transbronchial lung biopsy varies among various parenchymal lung diseases. In pulmonary sarcoidosis and lymphangitis carcinomatosa, a diagnosis can be obtained in up to 80% of patients. This method is considered inadequate, however, in identifying more complex histological patterns such as usual interstitial pneumonitis or nonspecific interstitial pneumonitis. Introduction of the 'jumbo forceps' and of a more 'surgically oriented' procedural setting (patients deeply sedated and intubated) allowed larger and more numerous lung specimens to be obtained without a significant increase of complications such as pneumothorax or bronchial bleeding. However, the possibility to obtain enough parenchymal tissue for a morphological diagnosis of complex patterns remained unmet. Recently, the use of cryoprobes has achieved a significant impact on this issue allowing to obtain large quantity of tissue. Recent studies document that with transbronchial cryobiopsies the diagnosis of usual interstitial pneumonitis can be made confidently by pathologists with a good inter-observer agreement. Pneumothorax is the main complication (reported in up to one fourth of cases in some series); bronchial bleeding is easily controlled using Fogarty balloon. Transbronchial cryobiopsy is a promising new technique that may become a valid alternative to surgical lung biopsy in the near feature.