Morphometrical analysis of transbronchial cryobiopsies

The recent introduction of bronchoscopically recovered cryobiopsy of lung tissue has opened up new possibilities in the diagnosis of neoplastic and non-neoplastic lung diseases in various aspects. Most notably the morphological diagnosis of peripheral lung biopsies promises to achieve a better yield with a high quality of specimens. To better understand this phenomenon, its diagnostic options and perspectives, this study morphometrically compares 15 cryobiopsies and 18 transbronchial forceps biopsies of peripheral lung tissue a priori without considering clinical hit ratio or integration of results in the clinical diagnostic processing. Cryotechnically harvested specimens were significantly larger (mean: 17.1 ± 10.7 mm2 versus 3.8 ± 4.0 mm2) and contained alveolar tissue more often. If present, the alveolar part in cryobiopsies exceeded the one of forceps biopsies. The alveolar tissue of crybiopsy specimens did not show any artefacts. Based on these results cryotechnique seems to open up new perspectives in bronchoscopic diagnosis of lung disease

Pulmonary fibrosis and the many faces of UIP

Interstitial lung diseases (ILDs) represent a heterogeneous group of clinical entities among which disease of unknown causes may mimic ILDs due to known causes [ 1 ]. Clinical, radiographic and histopathology presentation can largely overlap between different entities and a multidisciplinary approach is proven to be essential in composing the puzzle to reach the most likely clinical diagnosis in each single patients [ 2 ]. The defi nition of specifi c radiographic (on chest high-resolution computed tomography, HRCT) and histopathology (on lung surgical lung biopsy, SLB) patterns has provided a common terminology in the fi eld of ILDs in the tentative of classifying entities presenting with distinctive features. These patterns have been proposed in the classifi cation of idiopathic interstitial pneumonias (IIPs) [ 3 ], and then have been applied to describe ILDs due to secondary known causes, particularly those related to connective-tissue diseases. Among all these patterns, the usual interstitial pneumonia (UIP) pattern has received more emphasis, in particular since it identifies patients with idiopathic pulmonary fibrosis (IPF), as outlined in the most recent evidence based international guideline [ 4 ]. In this document, specific HRCT and SLB criteria for the defi nition of a defi nite UIP pattern have been proposed and since then they have been widely used as reference standard both in clinical practice and in the defi nition of eligibility criteria for randomized clinical trials. However, while a defi nite UIP pattern can be diagnostic for IPF in the proper clinical context, it is well known that the same pattern can be present in fibrotic lung diseases other than IPF, with important consequences in terms of therapeutic management and prognosis. This chapter will provide an overview on how the UIP pattern is defined, both on radiologist’s view and on pathologist’s view, along with elements that might be helpful in distinguishing an idiopathic UIP pattern from similar appearance in secondary diseases