The phrase “precancerous mouth cancer” is an inaccurate term for conditions that are not oral cancer. However, these conditions do have a higher than average chance of transforming into oral cancers.

Examples of these precancerous conditions include leukoplakia and erythroplakia.

Doctors and researchers may refer to mouth cancer as oral cancer.

This article will discuss oral precancers such as leukoplakia, erythroplakia, and other conditions. It will also describe how doctors diagnose and respond to precancerous mouth cancer.

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Some people use the term “precancerous mouth cancer” to describe conditions that are not oral cancers but which put a person at a heightened risk of developing them. However, this term is inaccurate.

Although these conditions exist, doctors and scientists do not call them precancerous mouth cancers.

A more accurate term for them is “mouth precancer.” However, according to a 2021 article, the scientifically best term for these conditions is “oral potentially malignant disorder (OPMD).”

There are several OPMDs. Although an individual with an OPMD is not guaranteed to develop oral cancer, doctors may test for this condition after diagnosing an OPMD.

Oral leukoplakia is an OPMD. Researchers estimate that it transforms into cancer in between 0.1% and 17.5% of cases.

According to a 2022 review, oral leukoplakia is any patch or plaque with the following qualities:

  • it develops within the mouth
  • it is white
  • it is undefinable as any other lesion

Tobacco use is the most common cause of oral leukoplakia. However, there are other risk factors for this condition, including:

  • drinking alcohol
  • chronic irritation, such as from ill-fitting dentures
  • frequent dental infections or chronic candidiasis
  • exposure to ultraviolet radiation

Oral leukoplakia is more common in males and older individuals.

Erythroplakia is a different OPMD.

Although a 2022 study describes it as rare, scientists estimate that erythroplakia could become cancerous in around 85% of cases.

The same study defines this condition as any patch with the following properties:

  • it develops within the mouth
  • it is well-defined
  • it is uniformly red
  • it is velvety in texture

Scientists believe tobacco smoking and alcohol consumption may be the main causes of erythroplakia.

As with oral leukoplakia, it more commonly affects older males.

Scientists have discovered many OPMDs.

The above 2020 study lists these as follows:

Other conditions may be OPMDS, although scientists remain uncertain about their exact relationship to oral cancer. These conditions include:

  • lupus erythematosus, a chronic autoimmune disease that causes widespread inflammation
  • actinic keratosis, a precancerous growth on the skin
  • dyskeratosis congenita, a genetic condition affecting many areas of the body, such as the nails, skin, and mouth
  • epidermolysis bullosa, a group of inherited conditions that causes fragile skin that tends to blister easily
  • chronic Candida infections, a fungal infection

An individual with these conditions may wish to speak with their doctor about their risk of developing mouth cancer.

People with Fanconi’s anemia — a genetic disease that commonly affects the bone marrow — also have an increased risk of developing lip cancer. This is because of an abnormality in the DNA’s repair mechanism.

Correctly diagnosing OPMDs can be an important first step in diagnosing a potential oral cancer.

This is important because an earlier diagnosis greatly improves the outlook for people with mouth cancer.

Doctors and dentists should be aware of the existence of OPMDs. Both types of healthcare professionals should provide screening tests for these conditions.

Additionally, doctors and dentists receive training to identify OPMDs according to their appearance.

If a dentist suspects someone’s mouth lesion is an OPMD, they will refer them to a healthcare professional who will likely suggest a biopsy.

This involves removing a small sample of the possible OPMD that undergoes testing to look for cancer cells.

Sometimes, doctors or dentists want to remove or correct mouth irritants before a biopsy. They may schedule another appointment in around 2 weeks.

These irritants include:

Since these irritants can cause lesions that look like OPMDs, healthcare professionals may want to rule out their involvement before suggesting a biopsy.

If the biopsy results suggest mouth cancer, doctors will discuss treatment options with the person.

Scientists have developed several ways to treat oral cancer. However, the most common form of treatment is surgery.

Doctors sometimes combine this with radiotherapy, chemotherapy, or immunotherapy.

This section answers some frequently asked questions about precancerous mouth cancer or OPMDs.

Where does mouth cancer usually start?

It may be difficult to tell where oral cancer starts. However, according to a 2018 study, the tongue is the most common subsite of oral cancer.

A subsite is the specific area where oral cancer is present within the mouth.

Other subsites include:

  • the lips and buccal mucosa, or inside cheeks
  • the gingiva, or the gums
  • the floor of the mouth
  • the hard palate
  • the retromolar trigone, or the area behind the third molar tooth

What is the difference between precancerous oral cancer and oral cancer?

Oral precancers, or OPMDs, are conditions that are not oral cancers but have an elevated risk of developing into oral cancers.

Oral cancer is cancer that develops in any part of the mouth. This may include the gums, the inside of the cheeks, or the tongue.

Oral cancers can develop in many ways.

Sometimes, they derive from conditions that are not themselves oral cancers but have an elevated risk of becoming them. These are OPMDs, or oral precancers.

There are many different kinds of OPMD. For instance, oral leukoplakia is a white plaque-like lesion, while erythroplakia is red and velvety.

Though scientists have cataloged many OPMDs besides these, they remain unsure about some conditions and their relationship with oral cancer.

Doctors and dentists receive training to identify OPMDs according to their appearance.

Since these conditions resemble others, they may sometimes provide dental treatment to the individual with a suspected OPMD.

If the lesion disappears after this treatment, it may not have been an OPMD. If the lesion persists, doctors will recommend a biopsy.

The biopsy could confirm that someone has already developed oral cancer. It could also alert doctors to those at a higher risk of developing mouth cancer.