Improving outcomes for people with skin tumours including melanoma

Genetic predisposition to MM may also occur, with approximately
1–5% of patients with MM having a family history. Rare high-risk
genes occur that are inherited as autosomal dominants, and these may
manifest as multiple primary tumours in an individual and/or
clustering in families. Most families with these genes in the UK are at
increased risk of MM alone. In other countries there also appears to
be an increased risk of pancreatic cancer.
Improving Outcomes for
People with Skin Tumours
including Melanoma
Management of special
groups
The incidence of MM in the UK is around 10 per 100,000 per annum.
Allowing for 80% survival and a mean age of 51 at diagnosis, an
estimated population prevalence is around 1 in 10,000. The majority
of these will have high-penetrance genes resulting in a lifetime risk of
developing MM of between 60% and 80%.
In the general UK population, individuals with multiple moles (the
atypical mole syndrome [AMS]) are at increased risk of MM and this is
thought to be genetic, probably due to low-penetrance susceptibility
genes. The phenotype is, however, common and patients with the
AMS require education about prevention, both primary (sun
avoidance) and secondary (signs and symptoms). Patients with AMS
have a relative risk of MM of around 10 compared with those who
have very few moles. The lifetime risk of MM in the UK is
approximately 1 in 150; patients with AMS have an estimated 1 in 20
lifetime risk compared with a person with an average number of
moles. Their risk is lower when compared, for example, with those
with XP, but as 2% of the general population have the AMS these
patients ‘explain’ a significant proportion of the disease.
6
Organ transplant patients
There is epidemiological evidence that patients who have had an
organ transplant are at high risk of developing all types of skin
cancers as a result of long-term immunosuppression. The risk
increases with time following the transplant and is higher in older
patients and white-skinned people who have had excessive sun
exposure. These patients are especially at risk of developing SCC of
the skin and often have multiple and fast-growing tumours, which
may pose difficulties in their management. As organ transplant
recipients live longer, so the prevalence of skin tumours with
metastases in this population will increase.
Guidance on cancer services: skin tumours including melanoma
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