Bowen's Disease is characterized by a precancerous, slow growing skin malignancy. The major symptom is a red-brown, scaly or crusted patch on the skin which resembles psoriasis or dermatitis. It may occur on any part of the skin or in the mucous membranes.

Bowen's disease typically presents as a gradually enlarging, well demarcated erythematous plaque with an irregular border and surface crusting or scaling. BD may occur at any age in adults but is rare before the age of 30 years - most patients are aged over 60. Any site may be affected, although involvement of palms or soles is uncommon. BD occurs predominantly in women (70-85% of cases); about three-quarters of patients have lesions on the lower leg (60-85%), usually in previously or presently sun-exposed areas of skin.

Bowen's Disease is also defined as Bowen's among dermatologists. Bowen disease is a squamous cell carcinoma (SCC) in situ with the latent for significant lateral spread. Pre-invasive means that there are cancer cells there. But they are enclosed to the outermost layer of skin, the epidermis. Most doctors and authorities regard Bowen's as a type of squamous cell carcinoma; although some regard it as a precancer.

Causes

The exact cause of Bowen's disease is unknown. Like many forms of cancer, long-term sun exposure may be a cause. The skin usually indicates sun damage, such as wrinkling, changes in pigmentation, and loss of elasticity. Ingestion of arsenic has been associated with cases of Bowen's disease found in skin areas unexposed to light or mucous membranes.

Bowen's disease may turn cancerous

In most cases, Bowen's disease remains confined to the upper layer of the skin (epidermis). However, there is a small risk that the affected cells may migrate deeper into the skin layers. Once Bowen's disease escapes the epidermis, it can become a more aggressive form of skin cancer. If a patch of Bowen's disease becomes raised, tender or bleeding then it may have turned cancerous and will need medical attention.

Treatment

Surgical excision is the common treatment for small SCC in situ which involves the removal of approximately one quarter of an inch past the edge of the cancer. With larger cancers Mohs surgery has the highest rate of all known treatment methods and may be necessary although they can also have surgical excision.

Several treatments are available for Bowen's disease, such as freezing it, scraping it off the skin (curettage), and surgical removal. In some cases a cream known as 5-fluorouracil (Efudix cream) or an alternative cream called imiquimod (Aldara) may be used. Photodynamic therapy is available in some clinics now (see below). Radiotherapy (X-ray treatment) is being used less often.

Curettage ? the lesion is scraped off the skin. It may also be used with cauterisation, where the skin is lightly burnt with and electric current. Recurrence is slightly more likely than with surgery.