You use your mouth every single day to eat and speak and laugh. The mouth comprises numerous complex components and tissues, all of which can succumb to health problems. Some problems that affect your mouth are mostly harmless and will get better on their own. Other oral problems can present serious health issues that can affect your everyday life and potentially spread to other parts of your body.

On one spectrum, you have oral cancer, characterized by the uncontrolled growth of cells in the mouth and throat. At the other end of the spectrum, you have canker sores, which are relatively harmless, though highly irritating. Identifying the two can be difficult as there is some overlap in presentation. Learn more about identifying oral cancer vs canker sore below.

What Is Oral Cancer?

Oral cancer and oropharyngeal  cancer start in the cells of the mouth and the middle part of the throat. Cancer is characterized by the abnormal growth of cells, resulting in growths that can take up valuable oxygen and nutrients or crowd out and cut off oxygen to nearby tissues and organs, resulting in severe health problems. Considering that your mouth serves several important functions, like eating, breathing, and talking, oral cancers can have a severe impact on your life and personal health.

Oral cancers affect all parts of the oral cavity, including:

  • The lips
  • The inside lining of the lips and cheeks
  • The gums
  • The teeth
  • The front two-third of the tongue
  • The area under the tongue
  • The hard palate (the roof of the mouth)
  • The area behind your wisdom teeth/molars

The oropharynx is the middle portion of your throat located behind the oral cavity. Cancers of the oropharynx include:

  • The base of the tongue (the rear one-third of the tongue)
  • The soft palate (back portion of the roof of the mouth)
  • The side and back walls of the throat
  • The tonsils

Oral cancers are identified based on the type of cells that are affected. While the oral cavity and oropharynx comprise numerous different types of cells, almost all oral cancers are squamous cell carcinomas. This type of cancer affects the flat, thin cells that make up the lining in your mouth and throat. Other types of oral cancer can affect the gland responsible for producing saliva. Your tonsils and the base of your tongue also contain lymph tissue, which is part of the immune system, that can become cancerous.

Symptoms of Oral Cancer

Signs and symptoms of oral cancer will vary from person to person. What makes oral cancer difficult to identify is that the symptoms are easy to mistake for other common conditions. Symptoms for oral cancer may include:

  • A sore on your mouth or lips that does not heal
  • Persistent pain in the mouth
  • A noticeable lump or thickening in your mouth, lips, or cheeks
  • A noticeable lump in the back of your throat
  • White or red patches on your gums, tongue, lining of the mouth, or tonsils
  • A sore throat
  • Problems with swallowing or chewing
  • Teeth feeling loose
  • Dentures that feel uncomfortable or start to fit improperly
  • General pain in your teeth
  • Numbness in your mouth
  • Unintended weight loss
  • Sudden changes to your voice
  • Persistent pain in your ears

These symptoms can be easily attributed to other conditions. Some of these may be associated with basic dental issues. These symptoms may also be caused by other types of cancer, so it’s important to consult your doctor if you experience any of the above symptoms or any general pain or discomfort in your mouth. You can also perform a self oral cancer screening to examine your mouth area to check for any signs of oral cancer. 

What Is a Canker Sore?

There are different types of mouth sores, from cold sore to canker sore that can all be painful. the one being discussed here is a canker sore. Canker sores are small, shallow lesions that appear on the lining of your mouth and lips. Canker sores are medically known as aphthous ulcers, and they typically appear as sores that are red around the edges with white or yellow centers. They are usually small, less than a millimeter in diameter, but at their largest, they may appear up to an inch in diameter.

As you can imagine by the name, canker sores can be painful, and depending on their location, they may make eating or talking uncomfortable.

The exact cause of canker sores is still not well known. Most experts believe that canker sores are caused by excess stress and/or minor injuries to the inside of your mouth (like biting your cheek). Some foods that are particularly acidic, like pineapples, citrus fruits, and tomatoes, may trigger canker sores or exacerbate existing canker sores. A sharp tooth or braces that rub against your mouth can also contribute to canker sores.

It’s important to note that canker sores are not caused by any sort of infection. This means that they are not contagious. Canker sores are also different from a cold sore or a fever blister. Cold sores are caused by the herpes simplex type 1 virus. Cold sores are fluid-filled blisters that more often appear outside the mouth, like around your lip or under your nose.

Differentiating Between Oral Cancer and Canker Sores

So what’s the difference between a mouth sore and oral cancer? To the uninitiated, differentiating between oral cancer symptoms and canker sores can be difficult, partly because one of the symptoms of oral cancer is sores in and around the oral cavity. However, being able to identify one over the other is essential to your well-being and peace of mind. Canker sores are completely harmless and generally don’t require any treatment, while oral cancer should be addressed as soon as possible to prevent spread and control symptoms.

Some of the main differences to look for:

  • Canker sores will typically go away on their own in a few days. At most, canker sores will take one to two weeks to heal. However, any sores or lesions from oral cancer will not heal or go away and may persist indefinitely.
  • Oral cancer does not always cause painful lesions. Patches in your mouth may appear red or white but present no pain or discomfort.
  • Canker sores always look flat with a white or yellow center. Lesions from oral cancer may be raised and appear white or red in color.
  • Canker sores can be painful enough to make chewing or eating uncomfortable but not impossible. Oral cancer can contribute to chronic, persistent problems with swallowing, talking, or chewing.

Essentially, canker sores do not last a long time and will go away on their own within a week or two. Oral cancer issues can be more chronic and have a significant effect on your health and everyday life. Either way, it’s important to take good care of your oral health and see your doctor with any concerns. 

Regardless, if you have any sores or experience any discomfort that makes your life harder, consult your doctor. They have the tools and knowledge to identify, diagnose, and may be able to offer insights into natural treatments, such as oral cancer alternative treatment, to address the issue. Even if it’s just a canker sore or another non-cancerous lesion, it’s worth seeing your doctor for peace of mind and to receive any necessary treatment. If you are experiencing oral cancer, however, you can visit the Immunity Therapy Center for different cancer treatment options.


  1. What Are Oral Cavity and Oropharyngeal Cancers?
  2. Signs and Symptoms of Oral Cavity and Oropharyngeal Cancer.
  3. Cleveland Clinic. Canker Sores. 
October 13, 2021

Dr. Carlos Bautista is a Board Certified Medical Doctor. He received his Medical Degree from Universidad Autónoma de Baja California and has more than 20 years of experience working with Alternative Medicine to treat cancer, autoimmune diseases, chronic degenerative diseases, and infectious diseases. He opened Immunity Therapy Center in 2007 with the goal of providing the highest quality medical care for more than 5,000 patients.

At Immunity Therapy Center, our goal is to provide objective, updated, and research-based information on all health-related topics. This article is based on scientific research and/or other scientific articles. All information has been fact-checked and reviewed by Dr. Carlos Bautista, a Board Certified Medical Doctor at Immunity Therapy Center. All information published on the site must undergo an extensive review process to ensure accuracy. This article contains trusted sources with all references hyperlinked for the reader's visibility.