Low-cost Screening and Image-guided Photodynamic Therapy (PDT) of Premalignant and Malignant Oral Lesions

Subject Inclusion Criteria 1. One grossly visible OPML, with histopathologically confirmed diagnosis of moderate, severe, and carcinoma in situ measuring ≥ 10 mm in diameter. 2. Willing and available for follow-up for at least one year and at prerequisite time intervals. 3. All patients above the age of 18 years and willing to voluntarily give a signed informed consent. 4. Karnofsky Performance Score above 80 or ECOG 0 or 1. 5. The subjects meeting the following laboratory eligibility criteria during a time not older than 2 months before accrual * Hemoglobin level above or equal to 10% * WBC \>3000/mm3 * Platelets count \>100000/mm3 * Total bilirubin, AST (SGOT), ALT (SGPT) \< 1.5 times the Upper Limit Normal * eGFR \> 60 ml/min * Serum Creatine less than 2 times the Upper Limit of laboratory normal * INR/ PT and PTT within laboratory normal limits Exclusion criteria: 1. Hypersensitivity against active substances and porphyrins. 2. Known diagnosis of porphyria. 3. Simultaneous use of other potentially phototoxic substances (eg; tetracyclines, sulphonamides, fluoroquinolones, hypericin extracts). 4. Uncontrolled concurrent illness, including but not limited to ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, uncontrolled cardiac and renal diseases or psychiatric illness. 5. Subjects with inherited or acquired bleeding and clotting disorders 6. Women who are breastfeeding/ have a positive urine pregnancy test or are planning their family. 7. Patients who have taken supplements of retinol, beta carotene, vitamin E, Selenium, or other chemo-preventive therapy at least one month prior to the baseline visit. 8. Patients with histological evidence of no dysplasia, mild dysplasia, invasive carcinoma, and any active malignant disease. 9. Patients with behavioral and cognitive impairment. 10. Patients who are concurrently diagnosed and undergoing treatment for other head and neck cancers. 11. Patients with large lesions, which, in the investigator's opinion, may require reconstructive surgery after excision. 12. The subjects, in the opinion of the Institutional Principal Investigator, are not an appropriate candidate for study participation due to alcoholism and abstinence. 13. Patient who was in a clinical trial for 4 weeks before participation in the present trial.