Lung cancer. Immunofluorescent Light Micrograph of \stealth\" carcinoma cells of the lung. Carcinoma is a cancer that arises in epithelium, cells which line body organs. Here, normal lung epithelial cells stain green. Smaller carcinoma cells (red) are termed \"stealth\" cells for their ability to flatten out and hide among lung tissue. Cell nuclei stain blue. Lung cancer is a common form of cancer, associated with cigarette smoking. Immunofluorescence is a staining technique which uses antibodies to attach fluorescent dyes to specific tissues and to molecules within the cell. Magnification: x125 at 35mm size."