Can a tongue ulcer cause tongue cancer?

Not really: Tongue ulcers do not turn into cancers but they may be cancers to begin with.

Not likely: If the tongue ulcer is not from existing diagnosed cancer, then it is not likely. The ulcer should resolve in 10 - 14 days if its cause is a burn or herpes, or aphthous ulcer (under tongue). If it is none of these, you should check with your dentist.

Needs evaluation: Any lesion if not completely gone in 14 days should be clinically examined by a trained health care practitioner and biopsied if warranted or suspicious. Please don't rely on any internet searches or answers in order to self diagnose yourself. Typically, an oral surgeon would be the most likely choice for oral lesions.

No, but...: An ulcer will not morph into cancer. But in their early presentation oral cancers may appear similar to ulcers. Any lesion that has not completely disappeared in no longer than 2 weeks should be evaluated. Any white spots, patches, red areas, of even one day greater than 2 weeks duration must be evaluated. See your Dentist or an Oral Surgeon.