Measurement of hypoxia-related parameters in bronchial mucosa by use of optical spectroscopy.

RATIONALE: Tumor hypoxia has both prognostic and therapeutic consequences for solid tumors. We developed a novel noninvasive technique, differential path-length spectroscopy (DPS), which allows the measurement of hypoxia-related parameters in the superficial microvasculature of tissue. OBJECTIVES: The aim of this study was to measure the microvascular oxygenation of histologically normal endobronchial mucosa and of neoplastic lesions during bronchoscopy using DPS. METHODS: Sixty-four patients with known or suspected malignancies of the lung were studied. One hundred and five endobronchial lesions (38 histologically normal, 37 metaplastic/mild dysplastic lesions, and 30 invasive carcinomas) were detected by white and/or autofluorescence bronchoscopy and measured using DPS. RESULTS: We observed that bronchial tumors are characterized by a lower blood oxygen saturation and a higher blood content than normal mucosa. No differences were observed between normal and metaplastic/mild dysplastic mucosa. CONCLUSION: DPS is a new optical technique allowing the noninvasive study of endobronchial tumor hypoxia.