Laser-induced fluorescence imaging in localization of head and neck cancers.

Laser-induced fluorescence tumor imaging exploits the difference in tissue autofluorescence properties between normal and cancerous tissues. The effectiveness and reliability of fluorescence imaging with a lung imaging fluorescence endoscopy (LIFE) system for cancers in the head and neck were compared to those of white light endoscopy (WLE). Examinations by WLE and LIFE were conducted on 25 patients suspected for malignancy. Histologic diagnosis was confirmed by biopsy. Posttreatment evaluations were performed on 6 cancer patients identified by this study. By LIFE, all 16 cancerous lesions, including 2 occult cancers, were identified (100%), while WLE achieved only an 87.5% detection rate. LIFE (specificity 87.5%) was greatly helpful to WLE (specificity 50%) in differentiating inflammation from malignancy, though it failed to exclude granuloma. The results of this study suggest potential roles of LIFE in early detection, correct staging, and treatment evaluation of cancers in the head and neck.