Development and in vivo test of a miniature Raman probe for early cancer detection in the peripheral lung.

The management of cancer in the periphery lung is in critical need of new strategies. Here, the development and test of a novel miniature Raman probe capable of navigating the peripheral lung architecture is reported. The probe was 1.35 mm in diameter, with a minimum bend radius of 13 mm and had a large light collection area for its size. Peripheral lung Raman spectra were successfully obtained from normal tissue and cancerous nodule using the probe coupled to a home-made rapid Raman spectroscopy system with a fast integration time of 1 second and a low excitation power of 15 mW. This is the first time in vivo Raman spectra from the periphery lung being reported. The collected spectra showed lipid, protein and deoxyhemoglobin signatures that might be useful for classifying pathology. Large scale clinical study is planned to confirm the utility of this new technology for improving periphery lung cancer detection. Left: Radial ultrasound image of a peripheral lung nodule: size given by crosshairs D1 and D2. Right: Truncated Raman spectra of a cancerous nodule, whole blood, and normal peripheral airway tissue. Spectra were shifted on intensity scale for clarity.