Confocal Laser Endomicroscopy in Pleural Malignancies: A Comparison With Pathology

Novel optical imaging techniques such as confocal laser endomicroscopy (CLE) have emerged in recent years as techniques that actually enable in vivo real-time microscopic analysis of malignancies of the GI-tract and lung cancer. Through recent advances the probe became small enough to fit through a biopsy needle and can be used during CT-guided and endosonographic guided biopsies (EUS-FNA). Patients with intra-thoracic malignancies often require invasive procedures such as bronchoscopy, thoracoscopy, mediastinoscopy, transthoracic needle aspiration or surgical exploration to obtain a diagnosis. Intra thoracic malignancies encompass lung cancers, thymomas and malignant pleural mesothelioma. These tumors often present with pleural thickening, unilateral pleural effusion, mediastinal enlargement or a peripheral located mass in the lungs. Tissue collection of the suspected pleural thickening is required to assess a diagnosis and differentiate between the tumor types, to classify and to stage in a proper manner. To date, the different biopsy methods, such as CT-guided pleural biopsy, mediastinal biopsy, endosonography and thoracoscopy have their limitations in diagnosing these malignancies. Sampling errors frequently occur resulting in the common histological finding of 'non-specific pleuritic/fibrosis', which presents a great uncertainty for clinicians and patients. Novel microscopic imaging techniques such as CLE are capable of real time imaging on a cellular level. Data of CLE in intra-thoracic malignancies are lacking.