Precancerous conditions of the skin

Last medical review:

Actinic keratosis is a precancerous condition of the skin. Precancerous conditions of the skin are changes to skin cells that make them more likely to develop into cancer. Actinic keratosis is not yet cancer. But if it isn't treated, there is a chance that these changes may develop into a type of non-melanoma skin cancer called squamous cell carcinoma. Actinic keratosis is also called solar keratosis.

Actinic keratosis is caused by sun damage to the skin. It often appears as small, rough patches on the skin that feel like sandpaper. These patches can get bigger and turn red or brown. They may be itchy or burn. There may be many patches close together in one area. There is usually more than one area of actinic keratosis. Actinic keratosis most often develops on areas exposed to the sun, such as the face, ears, neck, bald scalp, arms and backs of hands.

Your doctor will do a physical exam of the skin to diagnose actinic keratosis. A punch biopsy or shave biopsy may be done if the doctor can't tell if it is actinic keratosis or skin cancer. Find out more about punch biopsy and shave biopsy.

Treatments

Treatments for actinic keratosis usually depend on the number of abnormal areas and where they are. Treatments include:

  • medicines applied directly on the skin as a cream or ointment (called topical therapy), such as fluorouracil (also called 5-fluorouracil or 5-FU), imiquimod (Aldara, Zyclara) and tirbanibulin (Onakta)
  • cryosurgery
  • curettage and electrodesiccation (C&E) (scraping with a sharp tool to remove an abnormal area, followed by applying an electrical current to stop bleeding and destroy any remaining abnormal tissue)
  • surgical excision with a shave biopsy (also called shave excision)
  • photodynamic therapy (PDT)

Expert review and references

  • Rob Bobotsis, MD, MSc SLI, FRCPC, DABD
  • American Cancer Society. What Are Basal and Squamous Cell Skin Cancers?. 2023. https://www.cancer.org/.
  • AVIR Pharma Inc. Product Monograph: Onakta. https://pdf.hres.ca/dpd_pm/00070641.PDF.
  • Healthwise Staff. Actinic Keratosis. HealthLink BC; 2023. https://www.healthlinkbc.ca/.
  • Marques E, Chen TM. Actinic keratosis. StatPearls [Internet]. Treasure Island, FL: StatPearls Publishing; 2023. https://www.ncbi.nlm.nih.gov/books/NBK557401/.
  • Yu SH, Rasar Young M, Leffell DJ, Christensen SR. Cancer of the skin. DeVita VT Jr, Lawrence TS, Rosenberg S. eds. DeVita Hellman and Rosenberg's Cancer: Principles and Practice of Oncology. 12th ed. Philadelphia, PA: Wolters Kluwer; 2023: Kindle version, [chapter 62], https://read.amazon.ca/?asin=B0BG3DPT4Q&language=en-CA.

Medical disclaimer

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