Keratinizing squamous dysplasia of the oral cavity

by Jason Wasserman MD PhD FRCPC and Zuzanna Gorski MD
July 17, 2024


Background:

Keratinizing squamous dysplasia is a condition characterized by abnormal growth and development of the squamous cells that line the oral cavity. In this condition, the squamous cells exhibit abnormal changes, including increased keratin production, which can lead to the formation of thickened, white, or red patches in the oral cavity. This condition is considered a precancerous lesion because it has the potential to progress to squamous cell carcinoma, a type of oral cavity cancer if left untreated.

What parts of the oral cavity are typically involved in keratinizing squamous dysplasia?

Keratinizing squamous dysplasia can occur in various parts of the oral cavity, including:

  • Tongue: Particularly the lateral borders and ventral surface.
  • Floor of the mouth: An area under the tongue.
  • Buccal mucosa: The inner lining of the cheeks.
  • Gingiva: The gums.
  • Hard palate: The roof of the mouth.
  • Lips: The inner surface.

Oral cavity

What are the symptoms of keratinizing squamous dysplasia?

The symptoms of keratinizing squamous dysplasia can be subtle and may include:

  • White or red patches (leukoplakia or erythroplakia): These are areas of abnormal tissue that can be seen on the mucosal surfaces.
  • Pain: Affected areas may be painful or sensitive.
  • Thickened or rough areas: The surface may feel rough or thickened due to increased keratin production.
  • Difficulty in chewing or swallowing: If the dysplasia is extensive, it may interfere with normal oral functions such as chewing and swallowing.
  • Numbness: There may be a sensation of numbness in the affected areas.

What causes keratinizing squamous dysplasia?

Several factors can contribute to the development of keratinizing squamous dysplasia, including:

  • Tobacco Use: Both smoking and smokeless tobacco are major risk factors.
  • Alcohol consumption: Heavy alcohol use can exacerbate the effects of tobacco and independently increase risk.
  • Chronic inflammatory conditions: Conditions like lichen planus can lead to chronic inflammation and increase the risk of dysplasia.
  • Immune suppression/immune deficiency: Conditions or treatments that suppress the immune system can increase the risk of dysplastic changes due to reduced immune surveillance. Patients who have undergone an organ transplant and receive immune-suppressing medications are at particularly high risk.
  • Betel nut chewing: Chewing betel nut (areca nut) is a significant risk factor, particularly in regions where this practice is common. Betel nut contains carcinogenic compounds that can lead to oral mucosal changes and dysplasia.

How is keratinizing squamous dysplasia graded?

Keratinizing squamous dysplasia is graded based on the degree of abnormal cell changes observed under the microscope. The grading helps determine the risk of progression to cancer and guides treatment decisions. The grading system includes:

  1. Mild dysplasia: The abnormal changes are limited to the lower third of the epithelium. The risk of progression to cancer is relatively low, and close monitoring with regular follow-up is typically recommended. Learn more about your pathology report for mild keratinizing squamous dysplasia.
    Mild keratinizing squamous dysplasia
  2. Moderate dysplasia: The abnormal changes extend into the middle third of the epithelium. Compared to mild dysplasia, it is more likely to progress, and treatment may involve removing the dysplastic area or more intensive monitoring. Learn more about your pathology report for moderate keratinizing squamous dysplasia.
    Moderate keratinizing squamous dysplasia
  3. Severe dysplasia: The abnormal changes involve more than two-thirds of the epithelium but do not extend through its full thickness. This stage carries a significant risk of progression to squamous cell carcinoma, and surgical excision of the affected area is often recommended to prevent cancer development. Learn more about your pathology report for severe keratinizing squamous dysplasia.
    Severe keratinizing squamous dysplasia

Early detection and appropriate management of keratinizing squamous dysplasia are important in preventing the progression to invasive cancer. Regular dental check-ups and prompt evaluation of any persistent oral lesions are essential for maintaining oral health and reducing cancer risk.

Is keratinizing squamous dysplasia associated with an increased risk of developing cancer of the oral cavity?

Yes, keratinizing squamous dysplasia is associated with an increased risk of developing squamous cell carcinoma, a type of oral cavity cancer. The grade of the dysplasia correlates with the risk of progression to invasive cancer. Therefore, early detection and appropriate management of dysplastic lesions are crucial in preventing the development of oral cancer.

About this article

Doctors wrote this article to help you read and understand your pathology report. If you have any questions, please contact us.

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