What is Bowen's disease and how is it treated?

Bowen?s disease (named after the doctor who diagnosed it)  is a localised skin growth which means that it is usually confined to one area. Other terms you may hear used in relation to it are intraepidermal carcinoma in-situ (cancer that is confined to the outer layer of the skin) or pre-invasive squamous cell skin cancer. Although they can be a nuisance for the vast majority of people with it they cause very little harm but for a few they can develop into a type of skin cancer called invasive squamous cell cancer. The risk of this happening is hard to asses but studies suggest 3 to 5 out of every hundred of untreated Bowen?s disease will develop into invasive squamous cell cancer. There are many effective treatments to prevent this happening.

It can appear anywhere on the skin but is commonest on the head, the neck and the skin of the lower leg. It usually appears  as a red scaly patch which may itch or bleed.

Bowen?s disease is most often seen in people in their 60s and 70s, and is about three times more common in women than men.  Long-term exposure to sunlight is a cause of some lesions but in many cases of Bowen?s disease there is no obvious cause.

Bowen?s disease is diagnosed with a biopsy. This involves a small part of the affected area being removed. A local anaesthetic is given to numb the area. And the sample is sent to the laboratory to be looked at under a microscope. A skin specialist (dermatologist) usually does this. If the result confirms Bowen?s disease there are different treatments which may be used

Watchful waiting.  As Bowen?s disease is usually very slow growing, and as only a small minority of cases ever change into a cancer, simply keeping a watch on the situation, with regular check-ups to make sure the lesion is not changing, is a perfectly acceptable approach.  This is especially true for older patients, with lesions on their lower legs, where healing of the skin after treatment can often be difficult

Surgery. This is suitable for small areas that can be removed under local anaesthetic.   Surgery is not appropriate for large areas 

Curettage and electrocautery. This means scraping away the area and using heat or electricity to stop any bleeding. A local anaesthetic is given before the doctor scrapes away the Bowen?s using a spoon shaped instrument called a curette. An electrically heated loop or needle is then applied to stop the bleeding (cauterise) from the wound and destroy any remaining abnormal cells. After this treatment, a scar that is different from your normal skin colour may develop.   Curettage is suitable for small patches of Bowen? disease.

Topical therapy. This is the use of a cream which is applied over a period of time to the affected area.  It is not unusual for the area to become inflamed and for it to feel uncomfortable during treatment.    For many years a fluorouracil (5FU) cream has been used for this but recently another drug, called imiquimod, is sometimes used as an alternative.

Radiotherapy. Radiotherapy treats Bowen?s disease by using high- energy x-rays which destroy the abnormal cells while doing as little harm as possible to normal cells. It works well for Bowen?s disease and may be useful in areas where surgery might be difficult or disfiguring (such as on the face).

Photodynamic therapy (PDT) is a newer treatment which is used for different skin conditions.PDT uses laser, or other light sources, combined with a light-sensitive drug (sometimes called a photosensitising agent) to destroy abnormal cells.

A photosensitising cream is applied to the affected area  usually four to six hours before  treatment with the light which  lasts about  20-45 minutes. Afterwards a dressing is  put on to cover the area and protect it from light Usually more than one treatment  is needed.   PDT may be a useful option for people with large areas of Bowen?s disease

Cryotherapy. It may be possible to remove the area by freezing it. This is called cryotherapy or cryosurgery. Liquid nitrogen is sprayed onto the affected area  to freeze it.  This can be uncomfortable and healing may be slow afterwards, so usually other treatment methods are preferred.