Bowen’s Disease or Squamous Cell Carcinoma in Situ (SCCiS)

What is Bowen's disease?

Bowen's disease (also called squamous cell carcinoma in situ, or intraepidermal carcinoma) is a growth of abnormal cells that stays within the epidermis, the skin's outer layer. It is a very early form of skin cancer, but because it has not grown into the deeper layers of the skin, it is not a serious condition. It does, however, need to be assessed and monitored.

Who gets it?

Bowen's disease is most common in older adults with fair skin and a history of long-term sun exposure. People with a weakened immune system, for example those taking long-term medicines that suppress the immune system after an organ transplant, are at higher risk.

What causes it?

In most cases, Bowen's disease results from years of ultraviolet (UV) exposure from sunlight or sunbeds. Rarer causes include previous radiotherapy, past exposure to arsenic and infection with certain types of human papillomavirus (HPV), which is the main cause of Bowen's disease in the genital area.

Is it hereditary or contagious?

It is not passed down in families as such, though risk factors such as fair, sun-sensitive skin can be. It cannot be caught from someone else, and allergy plays no part.

What does it look and feel like?

Bowen's disease usually appears as a well-defined, flat or slightly raised, red, scaly patch that grows very slowly, sometimes over years, and can reach several centimetres across. It may crust or ooze. It is usually painless, though it can be itchy. On brown and black skin, it may appear brown or darker rather than red.

It most commonly appears on sun-exposed skin, such as the face, scalp, neck, hands and lower legs, but it can occur anywhere. Some people have more than one patch. Because it is red and scaly, it is often mistaken for eczema, psoriasis or a fungal infection.

How is it diagnosed?

Bowen's disease is diagnosed by a dermatologist from its appearance, usually with a dermatoscope. A small skin sample (biopsy) may be taken under local anaesthetic to confirm the diagnosis, particularly if the patch is unusual or thickened.

What are the treatment options?

Dr Mounsey will examine the patch with a dermatoscope and may take a biopsy to confirm the diagnosis. There are several effective treatments, and the choice depends on the size and site of the patch. Options include creams such as 5-fluorouracil or imiquimod, cryotherapy and curettage, which he carries out himself, surgical excision, and photodynamic therapy. Small patches on the lower legs that are not changing may sometimes simply be monitored. He will discuss the healing time and the likely cosmetic result of each option.

What is the outlook?

The outlook is excellent. As it is limited to the skin's surface layer, Bowen's disease can be cleared completely. In around 5 in 100 cases, it can progress to an invasive squamous cell carcinoma, so any lump, ulcer, bleeding or pain developing within a patch should be checked promptly. People with Bowen's disease have often had significant sun damage, so regular skin checks and sun protection are important.

More information

British Association of Dermatologists patient leaflet: https://www.bad.org.uk/pils/squamous-cell-carcinoma-in-situ

This page gives general information only and is not a substitute for a consultation. Everyone's skin is different, and what is right for you will depend on your own circumstances. If you are worried about a skin problem, please book an appointment with Dr Mounsey or speak to your GP. If you have a mole or skin lesion that is changing, bleeding or growing quickly, please seek medical advice promptly.