Bowen’s disease is a skin disorder that can cause skin patches or plaques that may be precancerous in some people.

Doctors also call the condition squamous cell carcinoma in situ. Keep reading to learn more about Bowen’s disease, including the causes, symptoms, and treatment options.

Bowen’s disease is a skin condition that causes red, scaly patches to form on the skin due to skin cell changes affecting the outermost layers of the epidermis. Doctors consider these patches to be the earliest form of squamous cell skin cancer, according to the American Cancer Society.

Bowen’s disease closely resembles actinic keratosis, another precancerous skin condition that causes rough, red spots to appear on the skin. The main difference between the two conditions is that Bowen’s disease patches tend to be larger than actinic keratosis patches.

In addition to affecting the areas of skin that a person can easily see, Bowen’s disease patches can appear on the anus and genital areas. Doctors will refer to Bowen’s disease in these areas as Bowenoid papulosis or erythroplasia of Queyrat.

Bowen’s disease causes a person to develop slow growing skin lesions. The lesions may appear as red-brown patches or dry, scaly plaques.

These patches may also:

  • bleed or ooze pus
  • itch
  • be tender to the touch

Other skin conditions that Bowen’s disease can resemble include:

  • eczema
  • fungus
  • psoriasis
  • some other rashes

Although many people with Bowen’s disease only have one lesion, 10–20% of people with the condition develop multiple skin lesions in different areas of the body.

Sometimes, these skin lesions can become cancerous. For this reason, a person with Bowen’s disease should be aware of the signs that a skin lesion is cancerous. These signs include:

  • hardening of a skin lesion
  • a nodule that feels very tender to the touch
  • the appearance of a flesh-colored nodule or lump
  • a skin nodule that bleeds easily

If a person notices these changes to their skin, they should see a dermatologist immediately.

Doctors do not know the exact cause of Bowen’s disease, but they have identified some risk factors for the condition. These include:

  • aging
  • chronic arsenic exposure — arsenic may be present in contaminated well water and some manufacturing areas
  • chronic sun exposure
  • fair skin with significant sun exposure
  • a history of human papillomavirus, particularly strains 16, 18, 34, and 48
  • a weakened immune system, for example, in those who take steroids for extended periods, live with HIV, or have cancer

The condition occurs most frequently in Caucasian people over the age of 60 years, according to the National Organization for Rare Disorders.

Doctors consider several factors when treating Bowen’s disease. These include the location of any lesions, their appearance, and a person’s overall age and health.

Each treatment option has different risks and benefits, and a person should discuss these with a doctor.

Treatment options may include:

  • Cryotherapy: This treatment involves applying a freezing substance — argon gas or liquid nitrogen — to destroy skin cells.
  • Curettage: This surgical procedure uses special tools to burn the lesion and scrape it away from the skin.
  • Photodynamic therapy: A doctor applies a special drug to the Bowen’s disease lesion. The drug reacts to light exposure, damaging and destroying the skin cells.
  • Surgical removal: This approach involves removing the lesion and closing the incision. Some people opt for a special surgical approach called Mohs micrographic surgery, which helps preserve tissue. This option may be ideal for lesions on the head, neck, and fingernails.
  • Topical chemotherapy: Examples include topical applications of 5-fluorouracil and imiquimod 5%.

Doctors do not always recommend treating Bowen’s disease lesions. Sometimes, the lesions are slow growing.

If a person has other conditions that may affect their ability to heal following treatment, such as diabetes, a doctor may recommend watching and waiting to see how the Bowen’s disease lesion develops before treating it.

Minimizing a person’s sun exposure can help reduce the likelihood that they will experience Bowen’s disease. Examples of steps to follow include:

  • refraining from using tanning beds, which increase exposure to ultraviolet light
  • avoiding working outdoors under direct sunlight
  • wearing protective clothing when outdoors, including hats
  • wearing sunscreen with a sun protection factor (SPF) of at least 30 and reapplying it frequently

Limiting sun exposure, whenever possible, may help prevent Bowen’s disease. However, people who do not have a significant history of sun exposure can still get Bowen’s disease.

There are several types of skin cancer that all differ slightly, including:

  • basal cell carcinoma
  • squamous cell carcinoma
  • melanoma

In rare instances, Bowen’s disease can develop into squamous cell cancer. This type of cancer grows in the outermost layers of skin cells.

Squamous cell cancers are different due to their location. For example, basal cell cancers grow in the lower part of the epidermis.

Read more about basal cell and squamous cell carcinoma here.

Melanoma starts in the pigmented portion of the skin cells, which is called melanin. Read more about melanoma here.

According to a Cochrane Review, most people with Bowen’s disease have an excellent outlook.

The reason for this is that most skin lesions grow very slowly, enabling a person to seek treatment before a lesion potentially becomes cancerous. Furthermore, the treatment options for Bowen’s disease are numerous, and treatment is generally effective.

Bowen’s disease is a condition that causes one or more skin lesions that may sometimes have painful symptoms.

As the condition can develop into skin cancer, doctors may recommend surgical removal or other medical approaches to treat the skin lesions.

If a person is concerned that they have Bowen’s disease, or they notice changes to a Bowen’s disease lesion, they should speak to a doctor.