Mouth cancer can develop on the lips, gums, tongue, the roof and floor of the mouth and inside the lining of the cheeks. According to the Mayo Clinic, this type of cancer falls under the category of head and neck cancers. People who smoke, chew tobacco, drink excessively or have a history of head and neck cancers are at risk for developing this type of cancer. The National Cancer Institute states that there are telltale signs of oral cancer in the mouth and gums.
According to the National Cancer Institute, patches are a sign of mouth cancer. They can be white, red, or mixed red and white patches. White patches are called leukoplakia and are the most common. Although these patches can become cancerous, that not always happen. Individuals may also develop mixed red and white patches, or erythroleukoplakia. These have a higher chance of becoming cancerous than the white patches. The third type of patches are bright red, called erythroplakia. These are usually smooth and likely to become cancerous.
The National Cancer Institute reports that loose teeth may be a sign of cancer in the mouth or gums. If the individual uses dentures, the person may find that their dentures don't fit as well as they used to.
Bleeding may also be a sign of cancer in the mouth and gums. The National Cancer Institute states that bleeding can occur from any part of the mouth, including the gums. The person may develop a sore on the lip or inside the mouth, which may not heal after repeated treatments.
A lump in the neck is also sometimes a sign of mouth cancer. It may just be a thickening of the skin.
Other signs include numbness of the lower lip and the chin. The individual may also experience pain in the ear that does not cease. Difficulty or pain in swallowing may also occur.