 It is becoming increasingly apparent that oral cancers develop within wide fields of diseased tissue characterized by genetically altered cells that are widespread across the oral cavity and present in clinically and histologically normal oral mucosa. Complete removal of these lesions is difficult because high-risk changes frequently go beyond clinically visible tumor. In recognition of this, current best practice is to remove SCC with a significant width usually 10 mm of surrounding normal-looking oral mucosa. However, since occult disease varies in size such approach often results in over-cutting causing severe cosmetic and functional morbidity or under removal of disease tissue, as evidenced by frequent positive surgical margins and high local and regional recurrence - a failure of the best practice. 