Background: There is a rising trend of oropharyngeal cancer, but a easy, safe and non –invasive test to differentiate the benign from malignant lesion is still at an early stage. Bulk fluorescence is an important step in this regards. Auto-fluorescence from biological agents like collagen and NADH (Nicotinamide adenine dinucleotide-reduced form) tissues involves evaluating the biomolecular environment through optical spectroscopy. Aim of Study: To study the role of optical spectroscopy in differentiating the benign from the malignant oral lesions by detecting the change in the bulk fluorescence, especially of collagen and NADH. Method: A study of 28 patients with oropharyngeal lesion was done. In all 28 freshly excised tissues, bulk fluorescences were measured by optical spectroscopy. Later the same excised tissues were processed for histopathology as gold standard. Results: This study showed that bulk fluorescence of collagen is a good method of investigation with 64.29% sensitivity than bulk fluorescence for NADH, which is only 35.70%. Conclusion: Optical spectroscopy has a bright future in differentiating the benign and malignant oropharyngeal lesion. Furthermore, it can detect cancer at an early stage.

Keywords: Bulk Fluorescence; Collagen and NADH (Nicotinamide Adenine Dinucleotide-Reduced form); Oropharyngeal Lesions.