The prevention, diagnosis and referral of melanoma of
the skin
Scope of the guidance
This EGP Update item draws on the Royal College of Physicians
(RCP) / British Association of Dermatologists’ (BAD) guidelines
which promote the early diagnosis of malignant melanoma of the
skin. The information given here has been supplemented by
publications cited in the Further
reading section.
Source
Royal College of Physicians and British Association of
Dermatologists. The prevention, diagnosis, referral and
management of melanoma of the skin: concise
guidelines. Concise guidance to good practice series, No 7.
London: RCP, 2007
www.rcplondon.ac.uk/pubs/contents/f36b1656-cc74-4867-8498-cc94b378312a.pdf
Key Points
1. Background
- Melanoma is about ten times more common in white than
non-white populations.
- Melanoma is more common in women than men.
- The likelihood of developing a melanoma rises with age;
but a fifth of cases occur in young adults.
- The overall 5-year survival rate for malignant melanoma
in England and Wales is 78% in men and 91% in women; even higher in
Scotland – 85% for men and 94% for women. http://info.cancerresearchuk.org/cancerstats/types/skin/?a=5441
- In the UK population the most common site for melanoma is
the lower leg in women and trunk in men.
- The incidence of malignant melanoma in the UK has
increased over the last 25 years, but death rates have stayed more
or less the same.
- The thickness of the melanoma is the most powerful
prognostic factor. The Breslow thickness, extent of
ulceration and number of lymph nodes involved guide the nature of
the surgical management of a primary melanoma.
2. Risks
- A genetic predisposition probably accounts for 5-10% of cases
of melanoma.
- The predictors of melanoma are progressive change in size,
colour and shape of moles.
- Adults who were exposed to sun or suffered severe sunburn as a
child have an increased risk of developing melanoma – but not
necessarily at the site of their body that was most exposed to
sunlight.
- Those with fair skin, freckles, red or blond hair and green or
blue eyes have an increased risk.
- People with a large number of moles (benign melanocytic naevi)
are at risk- the more skin naevi (especially if atypical), the more
risk.
- Take a look at the Guidelines for the RCP/BAD and
www.sign.ac.uk/guidelines/fulltext/72/index.html
to read up on the characteristics and rating of risk factors.
3. Prevention
- Protect skin from the sun by avoiding direct sunlight – keeping
out of the sun and wearing clothing that covers the skin.
- Use a sunscreen with protection factor of ≥ 20 and five star
ultraviolet A protection as well. But the use of such sunscreens
may mask a person’s awareness of the extent of sun damage on their
skin if they prolong their exposure believing that sunscreen is
protecting them fully from skin cancer.
- Educate those at highest risk about limiting their exposure to
sunlight (take advantage of any local dermatological expertise in
promoting such self care).
4. Signs and symptoms
- Essentially you will be suspicious and consider referring
urgently if there is a change in size or irregular shape or colour
of a mole. In addition you will be concerned about a mole if there
is inflammation, oozing/ bleeding, change in sensation or the
diameter is ≥ 7 mms.
- You should refer a patient urgently with any new nodule which
is growing and is pigmented or vascular in appearance- or with a
new area of pigment in a nail or growth under a nail.
5. Types of
melanoma (see
source for pictures of different types)
- Superficial spreading melanoma is the most common type. This is
slow growing along the skin at first with an irregular edge and
variable pigmentation – there may be three or more different
colours (browns, reds, blacks or blue-blacks). As the melanoma
advances it becomes nodular and may ooze and bleed.
- Nodular melanomas have a vertical growth phase resulting in a
dome like shape and tend to be thicker than other types of
melanoma. They are more common in older people. The melanoma is
usually black or red and may become ulcerated.
- Lentigo maligna melanomas are slow-growing over many years, and
are usually found on the sun exposed areas of the face and head in
older people. They may look like a large irregularly shaped freckle
at first which gradually becomes larger, with a more sharply
defined shape and darker pigment than a normal freckle.
- Acral lentiginous melanoma is the rarest type of melanoma which
is usually found on a person’s palms or soles of their feet.
Practical
tips for the busy GP >>
EGP 1. May 2008