Rapid growth linked to childhood cancer

By JEREMY LAURANCE

Modern teenagers grow so fast they may be at higher risk of cancer, warn specialists.

Better diets and improved lifestyles contribute to rapid growth, which could be fuelling the rise in cancer. Among young people aged 13-24 cancer has increased by more than a quarter in 20 years and by almost half in the past three decades.

The disease is now the biggest natural cause of death in the age group. Some cancers, such as melanoma, have doubled and are clearly linked to changing lifestyles.

But for other common cancers among teenagers, such as leukaemia and testicular cancer (in boys), the causes remain mysterious. The incidence of teenage cancer rose at 1.2 per cent a year between 1979 and 2000.

At the third international conference on teenage cancer in London on Monday, Professor Archie Bleyer, director of community oncology at the University of Texas in the United States, said increases in young people's height and weight in the past half century were likely to contribute to the rise.

Growth was caused by cell division and cancer occurred when cell division went out of control, he said.

"We have grown faster to higher heights and wider weights. The result of this increasing growth rate ... means there are more chances for cancer to develop. It is the trade-off for a rising standard of living."

Studies had shown that a baby's size at birth was linked to its chances of getting cancer in childhood.

"The faster the baby grows in the womb and the bigger it is at birth the more likely it is to develop cancer in early life," Professor Bleyer said. "If it continues to grow rapidly it may be more prone to cancer later on."

Charles Stiller, of the University of Oxford's childhood cancer research group, said bone cancer was the only cancer which peaked in the teenage years, when the bones were growing fastest. Other common cancers in teenagers, such as testicular cancer, could also be linked to rapid rates of growth and cell division in adolescence.

The link had yet to be proved, Dr Stiller said. "Much less is known about the causes and risk factors than for cancer in older adults."

As young people had not suffered prolonged exposure to environmental agents, the likeliest cause of their cancer was a genetic susceptibility.

- INDEPENDENT