Bowen’s disease is a very early form of squamous cell skin cancer, which is easily curable. The main sign is a red, scaly patch on the skin.
Squamous cells make up the single outermost layer of skin. Although some of these cells are cancerous in Bowen’s disease, the cancer is usually contained in this surface layer. Bowen’s disease is sometimes referred to as ‘squamous cell carcinoma in situ’. Sometimes, the cancerous cells spread along the skin surface, but it is very slow-growing. Only occasionally (in less than 10% of patients) does Bowen’s disease invade the deeper layers of skin and turn into a type of skin cancer (called Squamous Cell Carcinoma), but this is only a risk if Bowen’s disease is left undiagnosed. It is important to get a proper diagnosis, as Bowen’s disease can look like other conditions such as psoriasis or eczema.
Always see your GP if you have a red, scaly patch of skin and don’t know the cause. If necessary, your GP will refer you to a dermatologist to have a skin biopsy, to determine the cause of your skin abnormality.
Which parts of the skin does it affect?
Bowen’s disease can grow anywhere on the skin, especially the legs, trunk or arms. It is most commonly found on the lower leg of elderly women. Occasionally it can affect the genital area. This type of Bowen’s disease is known as bowenoid papulosis.
What are the symptoms?
Bowen’s disease usually appears as a reddened scaly patch on the skin that is 1-3cm in diameter. This is not usually itchy. Sometimes there are raised spots or lumps that look like warts. The affected skin can be red and sore and may bleed. Bowenoid papulosis appears as a brown patch around the groin are or a white patch (leukoplakia) around the vagina or in the mouth.
Who is affected?
Bowen’s disease is more common in women than men, and usually affects older people in their 70’s-80’s. It tends to be seen on people who have had lots of sun exposure (one of the main causes), especially those with fair skin. It is also more likely to affect people who take medication to suppress their immune system (eg, those who have just had an organ transplant).
What are the causes?
The causes of Bowen’s disease are often unknown. It does not run in families and is not passed on to others. Most cases develop as a result of long-term exposure to the sun. However, this is not the only cause as Bowen’s disease can develop in areas of the skin not normally exposed to the sun.
You are also more at risk of Bowen’s disease if you have had radiotherapy in the affected area. Rarely, it is related to arsenic exposure. Bowenoid papulosis (affecting the genital area) may be caused by the same human papillomavirus that causes genital warts.
How is it treated?
If the patch is not troubling you, your doctor may advise monitoring it closely, as it is very slow-growing. If treatment is recommended, your doctor will take into consideration where the patch is on your body and the size, thickness and number of patches you have before deciding on the most appropriate procedure. They will also consider how well your skin is likely to heal afterwards – for example, skin on the lower legs tends to be tight, fragile and slow to heal.
Treatment options include:
- Imiquimod cream or chemotherapy cream such as 5-fluorouracil – this is applied to the affected skin regularly over a period of time. It may cause your skin to become red and inflamed before it gets better.
- Cryotherapy – liquid nitrogen is sprayed onto the affected skin to freeze it. The skin will feel very cold and it may be a bit uncomfortable. The patch will scab over afterwards and usually fall off within a few weeks, removing the affected skin.
- Electrocautery – the affected area of skin is scraped away under local anaesthetic and heat or electricity is used to stop any bleeding.
- Photodynamic therapy – a light sensitive cream is applied to the affected skin and a laser is directed onto the skin 4-6 hours later to destroy the abnormal cells. The treatment session lasts about 20-45 minutes. A dressing covers the area afterwards to protect it from light. You may need more than one session.
- Surgery – the abnormal skin is shaved off or curetted, stitches are not normally needed afterwards and the wound normally heals as a graze but may result in superficial scarring. The procedure only takes 10 minutes. It is not the best option if the patch is large or if there are a few patches.
Talk to your doctor about which treatment may be most suitable for you.
Caring for your skin afterwards
After treatment you will need follow up appointments with a dermatologist to see if you need further treatment.
If you had surgery to remove the patch followed by stitches, you will need to have stitches removed one to two weeks later. In the meantime if your patch starts to bleed or change in appearance or a new lump develops, see your GP or nurse for advice immediately. Do not wait for your follow up appointment. Always make sure you protect your affected skin from the sun – wear protective clothing and use a sunscreen with a high sun protection factor (SPF) of at least 30.
Bowen’s disease often grows very slowly over a period of months or years. You may just need to keep a close eye on the patch of skin and have regular check-ups to monitor it.
All the above treatments work well for Bowen’s disease and the cure rates are high.
If Bowen’s disease is not diagnosed and monitored it can eventually turn into squamous cell carcinoma in a small number of people.