The 7 Warning Signs of Mouth Cancer
The most common warning signs of mouth cancer are a sore that doesn't heal, a red or white patch, and a new lump or thickening. Early mouth cancer is often painless, which is why changes get overlooked. Most of these changes turn out to be something harmless, but any of them lasting more than two weeks should be examined by a dentist or physician, who can refer you for further tests if needed.
1. A mouth sore that won't heal
Canker sores and bites usually heal within one to two weeks. A sore or ulcer that is still there after two weeks needs to be looked at, especially if it doesn't hurt. Read about evaluation of mouth sores and patches.
2. Red or white patches
A white patch (leukoplakia) or red patch (erythroplakia) on the gums, tongue, cheeks or floor of the mouth can be precancerous. A patch that doesn't wipe off and doesn't go away should be examined.
3. A lump or thickening
A new lump, rough spot or area of thickened tissue in the mouth, or a lump in the neck, deserves an exam. Your dentist or physician will examine it and refer you for further testing if it needs it.
4. A sore throat or hoarseness that lasts
A sore throat that doesn't clear up, a feeling that something is stuck in your throat, or a change in your voice that lasts more than a couple of weeks can be a sign of a problem in the throat. These are worth raising with your physician.
5. Trouble chewing, swallowing or moving the tongue or jaw
New difficulty chewing, swallowing, speaking or moving your tongue or jaw, without a clear cause such as an injury, should be checked.
6. Numbness or pain
Numbness of the tongue, lip or another part of the mouth, mouth pain that doesn't go away, or ongoing pain in one ear can all be signs worth investigating. [1] [2]
7. Loose teeth or dentures that stop fitting
Gum disease is the most common reason teeth loosen. Teeth that loosen without an obvious cause, or dentures that suddenly stop fitting, can also signal a change in the jaw underneath and should be examined. [2]
How do you check your own mouth?
Once a month, in good light and in front of a mirror:
Remove any dentures.
Look at and feel your lips and the inside of your cheeks.
Stick out your tongue and look at the upper surface, sides and underneath. Lift it and look at the floor of your mouth.
Tilt your head back and look at the roof of your mouth.
Feel along both sides of your neck and under your jaw for lumps.
If you notice a change, note the date. If it is still there in two weeks, call your dentist or physician.
What happens at an oral cancer exam?
The dentist looks at and feels the tissues of your lips, mouth, tongue and throat, and feels your neck and jaw for lumps. It is painless and takes a few minutes. If something needs a closer look, the next step may be a recheck or a biopsy. Only a biopsy can confirm or rule out cancer. Learn how oral cancer screening works at our office. It is part of every comprehensive exam. Research on new treatments continues, such as APG-157, an investigational plant-based drug, but finding changes early is still the most useful step.
Where can you have a mouth change checked in Jacksonville?
If you have noticed any of these signs for more than two weeks, don't wait for your next routine cleaning. Contact our office or call 904-398-1549, and tell the staff what you have noticed so we can schedule you appropriately.
Sources
National Institute of Dental and Craniofacial Research. Oral cancer. Retrieved October 6, 2026.
American Cancer Society. Signs and symptoms of oral cavity and oropharyngeal cancers. Last revised March 23, 2026.
About the author. CJ Henley, DMD, is a general dentist in Jacksonville whose practice focuses on cosmetic and restorative dentistry, dental implants and dental care around head and neck cancer. His role is dental care and coordination with your medical team. He does not provide cancer treatment. Meet Dr. Henley.
CJ Henley, DMD, PA · 3675 Hendricks Avenue, Jacksonville, FL 32207 · 904-398-1549
Updated October 2026.