Chest 2019 May 7 [Link]

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

Abstract

BACKGROUND:

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.

METHODS:

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.

RESULTS:

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).

CONCLUSIONS:

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).