Bowen's Disease

What Bowen's disease looks like

• A flat or slightly raised red or pink patch, usually 1 to 3 cm across, but can be larger
• Scale or crust on the surface
• A well-defined, often irregular edge
• Slow growth over months to years
• Usually painless, sometimes mildly itchy
• Can be single or multiple
• In darker skin, it may appear brown or gray

It is commonly found on the lower legs of older women, and on the head, neck, hands and other sun-exposed skin. It can also occur on the genitals, where it may be called erythroplasia of Queyrat (on the penis) and is often linked to HPV.

Bowen's disease vs similar conditions

Causes and risk factors

• Long-term sun exposure, the main cause
• Fair skin that burns easily
• Older age
• Weakened immune system, such as after organ transplant or with immunosuppressive medicines
• Human papillomavirus (HPV), particularly in genital and nail-area lesions
• Previous radiotherapy
• Arsenic exposure, historically through medicines or contaminated well water

Diagnosis

A dermatologist can often recognize Bowen's disease by its appearance and with dermoscopy, a magnified view that shows characteristic dotted or coiled blood vessels. A skin biopsy confirms the diagnosis and checks that the cancer has not invaded deeper layers. Biopsy is especially important if the patch is thickened, ulcerated or in an unusual site.

Treatment

Treatment choice depends on the size, number and location of patches, healing ability of the skin (the lower legs heal slowly) and the person's preferences.

• Cryotherapy: freezing with liquid nitrogen, good for small, single patches on areas that heal well.
• 5-fluorouracil (5-FU) cream: applied once or twice daily for several weeks; causes redness and crusting before healing.
• Imiquimod cream: stimulates the immune system to clear the abnormal cells.
• Photodynamic therapy (PDT): a light-sensitizing cream followed by red light; good for large patches and the lower legs, with good cosmetic results.
• Curettage and cautery: scraping off the patch under local anesthetic.
• Surgical excision: cutting out the patch, which also provides tissue to confirm complete removal.
• Mohs surgery for difficult sites such as the fingers, nails or genitals.
• Observation may be reasonable for slow, thin patches on the lower legs of very elderly or frail people.

Cure rates are high, often 80% to 90% or more, though recurrences can occur and may need further treatment.

Outlook and follow-up

Bowen's disease has an excellent outlook when treated. Because people with Bowen's disease have had significant sun damage, they are at higher risk of other skin cancers, so regular skin self-checks and periodic dermatology reviews are recommended.

Prevention

• Use broad-spectrum sunscreen SPF 30 or higher on exposed skin.
• Wear hats, long sleeves and sunglasses.
• Avoid the midday sun and never use tanning beds.
• Check your skin monthly and report any patch that persists for more than a month.

Frequently asked questions

Is Bowen's disease cancer?

Yes, it is an early form of skin cancer: squamous cell carcinoma in situ, meaning the abnormal cells are confined to the top layer of the skin. It is not dangerous at this stage, but about 3% to 5% of untreated patches become invasive squamous cell carcinoma, so treatment is usually recommended.

What does Bowen's disease look like?

It looks like a flat, red or pink, scaly patch with a clear edge, usually a few centimeters across, slowly growing over months or years. It often appears on the lower legs, face, scalp or hands. It is commonly mistaken for eczema or psoriasis.

Can Bowen's disease spread?

In its in situ form it does not spread. If it progresses to invasive squamous cell carcinoma, signs include a lump, bleeding or an ulcer within the patch. Invasive SCC can spread, though this is uncommon when treated promptly.

What is the best treatment for Bowen's disease?

There is no single best treatment. Cryotherapy suits small patches, creams like 5-fluorouracil suit larger or multiple patches, photodynamic therapy works well on the lower legs, and surgery gives the most certain removal. Your dermatologist will consider the site and size of the lesion.