Methods and kits for assessing the presence of, and for detecting cancer, notably oral cancer, are disclosed. Such methods and kits use one or more lectins operably linked to a fluorophore, wherein the lectin binds differentially to cancerous and non-cancerous tissues, and wherein the fluorophore facilitates visualizing the differential binding. The lectins are applied to the oral mucosa of a subject, the fluorophore is exposed to light, and cancerous regions of the mucosa are visualized. In certain embodiments, the lectin specifically binds to one or more of a β-galactoside, an α- or β-N-acetylglucosamine, or a sialic acid moiety.