In vivo Observation of Lung Cancer Cells on Endobronchial Lesions using an Endocytoscopy

Objectives: Endocytoscopy is a new endoscopic imaging device for in vivo visualizing cellular structures. The aim of this study was to observe lung cancer cells using an endocytoscopy and compare them with the microscopic findings. Methods: Between July 2009 and April 2011, 12 patients with lung cancer (5 with squamous cell carcinoma, 4 with small cell carcinoma and 3 with adenocarcinoma) and 3 control subjects who had no abnormal findings in large airway were examined. The patients had endobronchial lesions of lung cancer. After conventional bronchoscopy, the lesions were stained with 0.25% methylene blue dye and examined with endocytoscopy. The endocytoscopic images of the lesions were compared with the corresponding microscopic findings of the biopsy and/or brushing specimen. In the same way, normal bronchial mucosa in the control subjects were examined by endocytosocpy and compared with the microscopic findings of the biopsy specimen. Results: Endocytoscopy showed columnar epithelial cells on the normal bronchial mucosa in the control subjects. These cells were arranged regularly. On the other hand, in patients with lung cancer, polymorphic or oval cells were observed in squamous cell carcinoma, and round or oval cells were observed in both small cell carcinoma and adenocarcinoma. The heterogeneity in the cell distribution was found. In quantitative analysis, the cell area (p<0.002) and the nucleus-cytoplasm ratio (p<0.002) of tumor cells in the endoscopic images were significantly higher than those of normal bronchial epithelial cells, respectively. Conclusion: Endocytoscopy was supposed to have the potential to provide in vivo microscopic diagnosis during bronchoscopy.