BOWEN’S DISEASE (SQUAMOUS CELL CARCINOMA IN SITU)

What are the aims of this leaflet?

This leaflet has been written to help you understand more about squamous
cell carcinoma in situ (Bowen’s disease). It tells you what it is, what causes it,
what can be done about it, and where you can find out more about it.

What is squamous cell carcinoma in situ?

Squamous cell carcinoma in situ, often called Bowen’s disease, is a growth of
cancerous cells that is confined to the outer layer of the skin. It is not a
serious condition, and its importance rests on the fact that, very occasionally,
it can progress into an invasive skin cancer known as squamous cell
carcinoma (see Patient Information Leaflet on Squamous Cell Carcinoma for
further information). For this reason, dermatologists usually treat, or at least
monitor, Bowen’s disease.

What causes it?

Most cases of Bowen’s disease develop as a result of long-term sun
exposure, and it is more likely in those receiving long term
immunosuppression medication. Very occasionally, Bowen’s disease may be
seen following radiotherapy, longstanding arsenic ingestion (very rare
nowadays) or on the genitals in association with the virus that causes warts
(the human papillomavirus). Bowen’s disease is neither infectious, nor due to
an allergy.

Is it hereditary?

No, but some of the factors that increase the risk of getting it, such as a fair
skin and a tendency to burn in the sun, do run in families.

What are its symptoms?

Often there are no symptoms, although the surface may catch on clothing.

What does it look like?

A patch of Bowen’s disease starts as a small red scaly area, which grows very
slowly. It may reach a diameter of a few centimetres across. It commonly
occurs on sun-exposed skin, especially the face, scalp and neck, as well as
the hands and lower legs. More than one area may be present. The
development of an ulcer or lump on a patch of Bowen’s disease may indicate
the formation of invasive squamous cell cancer.

How will it be diagnosed?

A patch of Bowen’s disease can look rather like other scaly skin conditions,
such as psoriasis. For this reason a biopsy (a small sample of skin) may be
needed to make the diagnosis.

Can it be cured?

Yes. As Bowen’s disease is confined to the surface of the skin, there are a
variety of ways in which this can be achieved (see below).

How can it be treated?

A number of treatments are available for Bowen’s disease:

• Freezing with liquid nitrogen. This is done in the clinic. It causes
  redness, puffiness, blistering or crusting, and may be slow to heal. It
  can be done in stages for large patches.
• Curettage. This involves scraping off the abnormal skin under a local
• anaesthetic. The area then heals with a scab, like a graze.
• Excision. The abnormal skin can be cut out, under local anaesthetic,
  provided it is not too large. This involves cutting around the lesion and
  stitching the skin which will leave a scar. If this method of treatment is
  chosen, you will be informed about the type of surgery planned and
  any other potential complications.
• 5-fluorouracil cream. This is a cream that may control or eradicate the
  disorder. There are different ways of using it, and, if it is felt to be the
• best treatment, the doctor who sees you will explain these to you. It
  works by killing the abnormal skin cells. This means that the skin will
  become red and look worse during treatment, and will then heal after
  the end of the course of treatment, once the abnormal cells have gone
• (see Patient Information Leaflet on 5-Fluorouracil Cream).
• Imiquimod (Aldara) cream. This was originally developed for the
  treatment of genital warts, but imiquimod cream has been found useful
  in treating Bowen’s disease. It also causes inflammation of the skin
  during treatment (see Patient Information Leaflet on Imiquimod
  Cream).
• Photodynamic therapy. A chemical is applied to the skin that makes
  the cells in the patch of Bowen’s disease sensitive to particular
  wavelengths of light. Light from a specially designed lamp is then
  shone onto the patch. This treatment can be painful and cause
  inflammation; however any inflammation should disappear within a few
  days (see Patient Information Leaflet on Photodynamic Therapy).
• Radiotherapy and laser are other therapies occasionally used for the
  treatment of Bowen’s disease, although radiotherapy is not used for
  patches on the lower leg.

A particular problem with Bowen’s disease is that it is frequently found on the
lower leg – where the skin is often tight and sometimes quite fragile, especially
in older patients. Healing there is slow. Many factors, therefore, play a part in
selecting the right treatment:

• The size and thickness of the patch
• The number of patches
• The presence of swelling of the legs
• The general state of the skin on the legs
• The patient’s preference

If the affected area is judged to be thin and not likely to cause problems, your
dermatologist may simply suggest that it is kept under observation in a clinic,
or in some cases by yourself or by your GP.

Self care (What can I do?)

• From now on, you should take sensible precautions to prevent
  additional patches of Bowen’s disease developing. This means:
• Protecting your skin with clothing, and not forgetting to wear a hat
  that protects your scalp, face, neck and ears, and a pair of UV
  protective sunglasses
• Spending time in the shade between 10am and 3pm when it’s
  sunny.
• Choosing a sunscreen with a high protection SPF (SPF 30 or
  more) to protect against UVB, and looking for the UVA circle logo
  and/or 4 or 5 UVA stars to protect against UVA. Apply plenty of
  sunscreen 15 to 30 minutes before going out in the sun, and
  reapply frequently, especially after swimming, and in accordance
  with manufacturer’s recommendations.
• Check your skin regularly for new patches.
• The smaller your patch of Bowen’s disease is, the better the results of
  treatment are likely to be. If you think another one is developing, see
  your doctor about it promptly.

If your patch changes in any way (e.g. bleeds, ulcerates or develops a
lump) contact your doctor as soon as possible as this could be the start
of an invasive skin cancer.

Vitamin D advice

The evidence relating to the health effects of serum Vitamin D levels, sunlight
exposure and Vitamin D intake remains inconclusive. Avoiding all sunlight
exposure if you suffer from light sensitivity, or to reduce the risk of melanoma and
other skin cancers, may be associated with Vitamin D deficiency.

Individuals avoiding all sun exposure should consider having their serum Vitamin
D measured. If levels are reduced or deficient they may wish to consider taking
supplementary vitamin D3, 10-25 micrograms per day, and increasing their
intake of foods high in Vitamin D such as oily fish, eggs, meat, fortified
margarines and cereals. Vitamin D3 supplements are widely available from
health food shops.

Where can I get more information about Bowen’s disease?

References:

Guidelines for management of squamous cell carcinoma in situ (Bowen’s
disease) (in production)

For details of source materials used please contact the Clinical Standards
Unit (clinicalstandards@bad.org.uk).

This leaflet aims to provide accurate information about the subject and
is a consensus of the views held by representatives of the British
Association of Dermatologists: individual patient circumstances may
differ, which might alter both the advice and course of therapy given to
you by your doctor.

This leaflet has been assessed for readability by the British Association of
Dermatologists’ Patient Information Lay Review Panel
BRITISH ASSOCIATION OF DERMATOLOGISTS
PATIENT INFORMATION LEAFLET
PRODUCED JUNE 2007
UPDATED MAY 2010, DECEMBER 2013,
JANUARY 2017
REVIEW DATE JANUARY 2020

Download PDF version  from the British Association of Dermatologists