Comparative study of ex vivo probe-based confocal laser endomicroscopy and light microscopy in lung cancer diagnostics.

BACKGROUND AND OBJECTIVE: Probe-based confocal laser endoscopy (pCLE) allows for real-time non-invasive histological imaging via bronchoscopy. Interpreting CLE images and correlating with traditional histopathology remains challenging. We performed an ex vivo study to evaluate the correlation between light microscopy findings and pCLE imaging of primary lung carcinoma. METHODS: Post-lobectomy specimens for lung cancer nodules were examined ex vivo by pCLE. The examined areas were marked with brilliant green dye, and the surrounding tissues were stained by methylene blue dye. Lung tissue segments were resected and histopathological specimens were generated with 50-µm thickness from the marked areas and stained with haematoxylin and eosin. Pathologists and pulmonologists reviewed the images for correlating features. RESULTS: Eighteen lobectomy specimens from 18 different patients were collected. Three primary features were observed in all samples using pCLE in the cancer surroundings: alveolar dystelectasis with thickening of alveolar walls, alveolar edema and a large amount of macrophages. The stromal and parenchymal components of the studied subtypes of non-small-cell lung cancer differed from each other. The stromal component for all nine adenocarcinoma specimens had a highly fluorescent field penetrated by dark hollows. All six squamous cell carcinoma specimens had the stromal component appeared as 'biparously' branching, highly fluorescent fibres. No stromal component was observed in any small-cell carcinoma specimen, and at low power field, the cellular component was dominant with an observed light scattering pattern. CONCLUSIONS: pCLE can identify lung carcinoma in ex vivo samples. Certain light microscopy features of lung carcinoma can be visualized with pCLE.

Meta-analysis and systematic review of mediastinal cryobiopsy versus endobronchial ultrasound-transbronchial needle aspiration (EBUS-TBNA) in the diagnosis of intrathoracic adenopathy.

Background: Endobronchial ultrasound (EBUS)-guided mediastinal/hilar cryobiopsy (MedCryoBx) is a relatively new modality, being combined with EBUS-transbronchial needle aspiration (TBNA) to improve yield in the diagnosis of intrathoracic adenopathy. This meta-analysis aims to investigate the diagnostic yield of MedCryoBx versus EBUS-TBNA for intrathoracic adenopathy. Methods: We conducted a systematic search using Google Scholar, Embase, and PubMed/MEDLINE for studies about a diagnosis of intrathoracic adenopathy using MedCryoBx and EBUS-TBNA. Two authors separately reviewed studies for inherent bias using the Quality Assessment Data Abstraction and Synthesis-2 (QUADAS-2) tool. Inverse Variance weighting for random effects methodology was used for meta-analysis. Pooled diagnostic yields overall and for subgroups were estimated. Complications of MedCryoBx were reviewed. Results: Ten studies with 844 patients undergoing either biopsy procedure were in the final analysis. A total of 554 patients underwent MedCryoBx and 704 patients EBUS-TBNA. Meta-analysis showed a pooled diagnostic yield of 91% (504 of 554) for MedCryoBx and 81% (567 of 704) for EBUS-TBNA, with odds ratio (OR) of 2.5 [95% confidence interval (CI): 1.6 to 3.91; P<0.001], with I2 of 20%. Subgroup analysis for benign conditions showed increased diagnostic yield with OR of 7.95 (91% MedCryoBx versus 58% EBUS-TBNA, P<0.001) with an I2 of 25%. Subgroup analysis for lymphoma showed a statistically significant increase in pooled diagnostic yield with OR of 11.48 (87% MedCryoBx versus 29% EBUS-TBNA, P=0.001). Mild bleeding (36.5%) without any intervention was the most common complication. Bleeding requiring intervention (0.7%) was noted in patients. Pneumothorax (0.4%) and pneumomediastinum (0.4%) were less common in this analysis. Conclusions: MedCryoBx is a very promising tool for the diagnosis of intrathoracic adenopathy. It has improved diagnostic yield over EBUS-TBNA in benign and possibly lymphoproliferative diseases, but less so in lung cancer. The complication rates with MedCryoBx are comparable to EBUS-TBNA.

First-in-human high-cumulative-dose stem cell therapy in idiopathic pulmonary fibrosis with rapid lung function decline.

Previous phase I studies demonstrated safety and some beneficial effects of mesenchymal stem cells (MSCs) in patients with mild to moderate idiopathic pulmonary fibrosis (IPF). The aim of our study was to evaluate the safety, tolerability, and efficacy of a high cumulative dose of bone marrow MSCs in patients with rapid progressive course of severe to moderate IPF. Twenty patients with forced ventilation capacity (FVC) ≥40% and diffusing capacity of the lung for carbon monoxide (DLCO) ≥20% with a decline of both >10% over the previous 12 months were randomized into two groups: one group received two intravenous doses of allogeneic MSCs (2 × 108 cells) every 3 months, and the second group received a placebo. A total amount of 1.6 × 109 MSCs had been administered to each patient after the study completion. There were no significant adverse effects after administration of MSCs in any patients. In the group of MSC therapy, we observed significantly better improvement for the 6-minute walk distance in 13 weeks, for DLCO in 26 weeks, and for FVC in 39 weeks compared with placebo. FVC for 12 months in the MSCs therapy group increased by 7.8% from baseline, whereas it declined by 5.9% in the placebo group. We did not find differences between the groups in mortality (two patients died in each group) or any changes in the high-resolution computed tomography fibrosis score. In patients with IPF and a rapid pulmonary function decline, therapy with high doses of allogeneic MSCs is a safe and promising method to reduce disease progression.

Confocal laser endomicroscopy for diagnosis and monitoring of pulmonary alveolar proteinosis.

BACKGROUND: The diagnosis of pulmonary alveolar proteinosis (PAP) is based on computed tomography, histology, and antibodies to granulocyte-macrophage colony-stimulating factor. The role of a novel technique for imaging cells and elastin during endoscopy, probe-based confocal laser endomicroscopy (pCLE), has not yet been investigated in PAP patients. The aim of the present study was to estimate the value of pCLE in the PAP diagnosis and treatment in comparison with the findings of high-resolution computed tomography (HRCT) before and after whole-lung lavage. METHODS: In vivo pCLE was performed during bronchoscopy in 6 male patients with PAP before and after whole-lung lavage. In certain lung segments, pCLE was followed by HRCT. RESULTS: During the in vivo pCLE, we found characteristic signs of PAP: a fluorescent floating amorphous substance in the alveoli lumen sticking to conglomerates along with alveolar macrophages. These features were present to a lesser extent after a whole-lung lavage. pCLE revealed specific PAP features not only in segments with crazy-paving and ground-glass opacity, but also in segments without HRCT findings. CONCLUSIONS: The alveolar imaging in PAP patients is able to reveal characteristic changes, both in the presence and in the absence of HRCT findings. Therefore, pCLE may be a helpful tool for the diagnosis and whole-lung lavage therapy. Our data prove that accumulation of lipoproteinaceous substances within the alveoli at PAP is a diffuse but not a patchy process.

The case of diagnostics of invasive pulmonary aspergillosis by in vivo probe-based confocal laser endomicroscopy of central and distal airways.

We present a case of 41-year-old patient with invasive pulmonary aspergillosis (IPA) in which probe-based confocal laser endomicroscopy (pCLE) imaging of central and distal airways was first performed in vivo. pCLE imaging showed the signs of complete or partial destruction of elastin network of alveolar wall with fibrillar branching fluorescent structures in the zone with typical IPA changes on HRCT.