Bowen's disease, known within the medical community as squamous cell carcinoma in situ, is a skin condition caused by the growth of cancerous cells on the outer-most layer of skin. It affects approximately four people per 100,000 every year. If left untreated, the disease may develop into squamous cell carcinoma, one of the most common forms of skin cancer.
However, this progression towards squamous cell carcinoma only occurs in less than five percent of untreated patients and the spread of the disease is very slow. Generally, bowens disease is not considered to be serious, because cure rates for the condition are extremely high, with various different treatment methods, including chemotherapy cream and surgical procedures, proving to be effective.
The primary risk factor for the development of squamous cell carcinoma in situ is prolonged exposure to the sun. Incidents caused by sun exposure are especially prevalent amongst those with fair skin.
Another risk factor is a weak immune system. Therefore, people who are taking medication which suppresses the immune system, such as recent organ transplant patients, may find themselves more likely to develop the disease. People who have recently undergone radiotherapy may also be more vulnerable.
A relationship exists between the disease and non melanoma skin cancers, a group of skin cancers which are not malignant melanoma. As a result, previous sufferers of a non melanoma skin cancer may also find themselves more prone to the development of the disease. Similarly, previous bowens disease sufferers may be more likely to develop a non melanoma skin cancer in future.
Women are more likely to be affected than men and the condition usually affects older people more than younger people, with the age group between 70 and 80 considered to be most at risk. It cannot be passed on to other people and there is no known genetic link.
The disease usually manifests in the form of a patch of red, scaly skin, typically around 1 to 3 centimetres in diameter. The skin may be sore to touch and can sometimes be itchy. In some instances, the skin may bleed and a scab may form over it.
Although the disease may appear anywhere on the body, it is most often found on the arms and legs, with the lower legs being the single most common location. It usually appears as a single, isolated patch of red skin, although in some cases there may be multiple patches.
Due to the similarities between bowens disease and other conditions, like eczema and psoriasis, GPs will generally refer patients on to a dermatologist for further testing.
After tests have been carried out, a dermatologist will confirm the diagnosis and begin to consider the various methods of treatment available to the patient.
Treatment of Bowen's disease is very effective and cure rates are very high. Several methods of treatment are available to patients, including:
The method of treatment used will usually be decided by a dermatologist in conjunction with the patient and will depend on factors like the number of patches on the skin, as well as the size and location of the patch(es).
On rare occasions, a specialist may recommend non-treatment of the disease and advise that it is closely monitored instead. This will usually happen in cases where the disease is in its early stages and the side-effects of treatment are considered too much of a risk for the patient's specific circumstances.
After treatment, patients may require follow up appointments with a dermatologist in order to assess whether or not further treatment is required. If treatment involved the use of stitches, patients will also need to return to their GP around one or two weeks later to have them removed.
The affected skin should be protected from the sun using protective clothing or sunscreen, which should be at least factor 30. If the patch starts to change in appearance, starts to bleed or forms a new lump, an appointment should be made with a GP as soon as possible.