The number of under-50s worldwide being diagnosed with cancer has risen by nearly 80 per cent in three decades. What’s going on?
When Catherine, Princess of Wales, revealed her cancer diagnosis earlier this year, she shocked the world.
But her personal health trauma has shone a light on a rising trend — younger people receiving diagnoses.
Dr Julie Sharp, head of health information at Cancer Research UK says: ‘There isn’t a definitive answer to what’s causing the rise, but preventable risk factors, genetics and improvements to early detection might all play a part.’
Changing lifestyles
The biggest killer of women between the ages of 30 and 50 is breast cancer — just over 10,000 women are diagnosed with breast cancer under the age of 50 every year in the UK.
Dr Sacha Howell, a consultant at The Christie NHS Foundation Trust, is researching breast cancer risk assessment in young women, a study that is funded by the Sarah Harding Breast Cancer Foundation. The Girls Aloud singer was Dr Howell’s patient, and it was her dying wish to find ways for early detection and prevention.
‘The data in the UK and the US does indicate there is a small but significant increase in younger women developing breast cancer,’ says Dr Howell.
He agrees that diet is part of this.
He says: ‘We've known for a long time that Japan has the world’s lowest incidence of breast cancer, but if a Japanese person emigrates to America, within two generations, their descendants have a similar risk of breast cancer as other American women. There could be many reasons for this but changes in diet are likely to contribute.’
Another change in societal behaviour has seen women delaying their first full-term pregnancy.
Dr Howell says: ‘The age of first pregnancy has increased from about 25 years in the 1970s to over 30 in the latest UK figures. We also have fewer children — we know the more times women give birth and the earlier the first birth, the lower the risk of breast cancer tends to be.’
He says the combination of diet leading to weight gain and earlier puberty, later motherhood and fewer children could be adding up to earlier breast cancer.
‘To put it simply,’ he says, ‘for every menstrual cycle where the body prepares for pregnancy, there is cell division within the breast. With each cycle, the chance of mutations occurring in the cells is heightened. When a woman develops cancer, it’s because there’s been a tipping point with these mutations, and cancer develops.’
Dr Howell stresses that the majority of women don't develop breast cancer, even if they've had a later pregnancy, or menstruated at a young age.
‘These factors can raise the risk, but in reality, it’s by a relatively modest amount,’ he explains. ‘Learning about the risk factors can be helpful in identifying those at increased risk so that we can start screening earlier and consider preventive approaches.’