Affluent families who take their children on foreign holidays where they are exposed to intense sunlight are contributing to soaring rates of malignant melanoma among the young.
The severest form of skin cancer, which causes 1,800 deaths a year, is rising fastest in people in their teens and twenties and is most common among the better-off, doctors said.
Severe sunburn in childhood is a key trigger for the cancer and the growth of foreign holidays, in winter and summer, is increasing the incidence of sun exposure in children.
Professor Jillian Birch, an expert on teenage cancer from Manchester University, told an international conference in London that melanoma was increasing at 4 per cent a year among 20- to 29-year-olds.
"We know melanoma is caused by intermittent exposure to intense sunlight and that exposure in childhood increases the risks of developing the disease up to 40 years later," she said. "The incidence of the disease rises with age but there is some evidence that in the over-30s it is plateauing. However, in the 15 to 29 age group it is increasing at a faster rate."
Melanoma has seen the fastest growth of any cancer with rates in all ages up by more than 40 per cent in a decade. The rise is blamed on the British fondness for spending long periods on beaches to get a tan.
Latest figures show there were 713 cases of melanoma in young people aged 15 to 24 between 1999 and 2003 in England. Almost twice as many cases occurred in the most affluent group compared with the most deprived, the conference, organised by the Teenage Cancer Trust, heard.
Professor Birch said: "The simple conclusion is that it is down to excess sun exposure in childhood. But in these very young people there is likely to be something else going on. We are probably looking at a combination of sun exposure and genetic susceptibility.
"It is not just Mediterranean holidays but skiing holidays, sunbeds and other elements of the affluent lifestyle. The message is sun protection. Use a sunscreen but, even more important, cover up and keep out of the midday sun."
Other increasing teenage cancers include testicular and ovarian cancer, brain tumours and lymphoma. One of the fastest growing cancers in women under 25 is cervical cancer, with 40 to 45 cases a year in England. The incidence is rising by 6.8 per cent a year in 15-19 year olds and by 1.4 per cent in 20-24 year olds. Rates are falling in women over 25.
Unlike melanoma, cervical cancer is linked with deprivation and is more common in the north of the country, suggesting that safe-sex messages are not getting through. A vaccine against human papilloma virus (HPV), which causes cervical cancer, is being introduced for 12-year-olds this year as part of the national vaccination scheme.
Professor Birch, director of the Cancer Research UK Paediatric and Familial Cancer Research Group at the University of Manchester, said: "Clearly the vaccination will come too late for some of them. We are talking small numbers but we don't want any teenage girl to suffer invasive carcinoma."
What to look out for
*Malignant melanoma is the most serious type of skin cancer. It can appear anywhere but the commonest sites are the back, legs, arms and face.
The first sign is either the appearance of a new mole or a change in the appearance of an existing mole. It may be a dark, fast-growing spot where there was not already a mole or an existing mole may change size, shape or colour and bleed, itch or redden. Moles are usually a single colour, round or oval in shape and not more than 6mm (a quarter of an inch) in diameter.
Melanomas have an irregular shape with a notched or ragged border, are more than one colour and often larger than 6mm. If you notice one or more of these characteristics, see your GP.