Confocal laser endomicroscopy (CLE) as a guidance tool for pleural biopsies in malignant pleural mesothelioma.

Chest 2019 May 7 [Link]

Wijmans L, Baas P, Sieburgh TE, de Bruin DM, Ghuijs PM, van de Vijver MJ, Bonta PI, Annema JT



Pleural biopsies in patients with suspected malignant pleural mesothelioma (MPM) are often inconclusive featuring fibrosis, resulting in repeat diagnostic procedures. Confocal laser endomicroscopy (CLE) enables real-time imaging on a cellular level. We investigated pleural CLE imaging as a biopsy guidance technique to distinguish malignant from benign pleural disease.


Prospective, multi-center study in patients with (suspected) MPM based on (PET)-CT imaging who were scheduled for pleural biopsies. Patients received 2.5ml fluorescein intravenously preceding the procedure. In-vivo -through the needle- CLE-imaging of the pleura and ex-vivo CLE-imaging of the biopsies were correlated with histology. CLE characteristics for various pleural entities were identified and their interpretability was tested by CLE-video scoring by multiple blinded raters.


CLE imaging was successfully obtained in 19 from 20 diagnostic pleural biopsy procedures (thoracoscopy (n=3), surgical excision (n=3) CT- (n=4) , ultrasound- (n=9), EUS-guided (n=1)) in 15 patients. CLE videos (n=89) and corresponding pleural biopsies (n=105) were obtained. No study related adverse events occurred. Tumor deposits of malignant pleural mesothelioma were distinguished from pleural fibrosis based on CLE imaging and recognized by raters (n=3). (IOA: 0.56 (95%CI 0.49-0.64).


CLE imaging was feasible and safe regardless of the biopsy method. Real-time visualization of pleural abnormalities in epithelial and sarcomatoid MPM, could be distinguished from pleural fibrosis. Therefore, CLE has potential as a guidance biopsy tool, to reduce the current substantial rate of repeat biopsy procedures, by identification of areas with malignant cells in vivo (smart needle).