title: Optical coherence tomography as an adjunct to flexible bronchoscopy in the diagnosis of lung cancer: a pilot study.
abstract: Lung cancer is the leading cause of cancer-related deaths in the United States and the second most common type of cancer in both men and women. Optical coherence tomography (OCT) scanning can generate high-resolution cross-sectional images of complex, living tissues in real time. The objectives of this study were to determine the feasibility of using OCT imaging during flexible bronchoscopy and to preliminarily assess the ability of OCT imaging to distinguish an endobronchial malignancy from normal endobronchial mucosa. A Niris OCT probe was introduced into the airways of patients with an endobronchial mass during flexible bronchoscopy. An investigational device exemption was approved by the US Food and Drug Administration for the use of the OCT system in this study. Conventional OCT scans of an endobronchial mass and a control area of normal bronchial mucosa were performed to generate real-time images in each patient. Following OCT imaging, the same sites were biopsied for pathologic correlation. We report on the first five patients enrolled. A total of 60 OCT images with corresponding endobronchial biopsy specimens were obtained. The average procedure time was 29 min. The histopathologic diagnoses of the endobronchial masses included two small cell carcinomas, one squamous cell carcinoma, one adenocarcinoma, and one endobronchial schwannoma. Microstructures of normal bronchial mucosa, including epithelium and lamina propria, were identified with OCT imaging. OCT scan features of malignancy included loss of normal, identifiable microstructures and subepithelial "optical fracture" of tissues. All patients tolerated the endobronchial imaging well without complications. Preliminary results suggest that OCT imaging is a technically feasible adjunct to flexible bronchoscopy in the diagnosis of lung cancer. This is the first reported use of OCT to generate images of endobronchial neoplasms during flexible bronchoscopy in the United States. This technology may in the future provide a noninvasive "optical biopsy," which could potentially guide the bronchoscopist to areas for biopsy or even obviate the need for conventional lung biopsies.
  
  
  BACKGROUND
  clinicaltrials.gov; Identifier: NCT01039311.
authors.affiliation: Division of Pulmonary/Critical Care Medicine, Oklahoma City Veterans Affairs Medical Center and University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104-5020, USA. rgmichel2@gmail.com
authors.forename: Ross G
authors.initials: RG
authors.lastname: Michel
authors.forename: Gary T
authors.initials: GT
authors.lastname: Kinasewitz
authors.forename: Kar-Ming
authors.initials: KM
authors.lastname: Fung
authors.forename: Jean I
authors.initials: JI
authors.lastname: Keddissi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D020680:Bronchoscopes; D001999:Bronchoscopy; D003937:Diagnosis, Differential; D004867:Equipment Design; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D041623:Tomography, Optical Coherence / Q000379:methods*