More British women are being diagnosed with breast cancer than ever before.
The NHS offers screening to women over 50
Figures from Cancer Research UK show that more than 40,000 women are now told they have the disease each year.
But more women are now surviving the disease - three out of four live five years or more after diagnosis.
In 2001, around 13,000 women died of the disease, down 21% on 10 years ago.
Experts at Cancer Research UK said the fall could be attributed to improvements in treatments and the success of the NHS screening programme.
Breast screening was introduced gradually in the UK between 1978 and 1997.
Changes in the size, shape or feel of your breasts
A new lump or thickening in one breast or armpit
Any puckering, dimpling or redness of the skin
Changes in the position of the nipple, a rash or nipple discharge
Pain or discomfort that is new to you and felt only on one side
At present, routine invitations for breast screening are sent to all women aged between 50 and 64 in the UK every three years. There are plans to extend this to women aged up to 70.
Professor Robert Souhami, Cancer Research UK clinical director, said the rise in the number of women being diagnosed with the disease is worrying.
"The increase in the number of women diagnosed with breast cancer is a matter of concern.
"However, research is beginning to uncover the factors which affect risk, and knowing who is at risk and why is the first step towards prevention.
"In the meantime, early detection remains very important in preventing deaths from breast cancer and it is essential that women are aware of this and attend for screening when they are invited"
Professor Jack Cuzick, head of Cancer Research UK's epidemiology, mathematics and statistics department at the Wolfson Institute for Preventive Medicine in London, said further work is needed to find out why more women are being diagnosed with the disease.
"The reasons behind the increase in incidence are more complex and we're just beginning to understand the risk factors.
"The levels of the female hormone oestrogen seem to be important but these levels depend on a number of other variables.
"We know that obesity in post menopausal women is a risk factor and that it can raise the levels of oestrogen.
"We also know that levels of obesity have been rising steadily in the past decade and this may be contributing to the upward trend.
"But many of the risk factors are difficult or impossible to control - genes play a role, and both late menopause and the early onset of periods are known to increase the risk.
"We need to do more to understand the risk factors and develop preventative strategies."
Clara Mackay, director of policy and research at Breast Cancer Care, said: "Although the incidence of breast cancer in UK appears to be rising, it is encouraging to see that death rates are down by 21% over the last decade."
She said women should not be alarmed by the figures.
"Women should not be unduly alarmed by the figures released today; however it does reinforce the importance of breast awareness, as we know the majority of breast symptoms are found by women themselves.
But she added: "The increase in incidence is a cause for concern and we urge decision-makers in the government and the health service to invest more resources around health promotion in this area and ensure that they take on these new statistics when planning treatment and care provision."
Delyth Morgan, chief executive of Breakthrough Breast Cancer, called for money to help fight the disease.
"It is essential more resources are invested in research and improvements in NHS services are built on with patient involvement.
"Breakthrough's recent patient survey reveals encouraging developments in breast cancer services but there is still room for significant improvement.
"That's why Breakthrough is campaigning for a health service truly sensitive to the needs of patient through Rights & Realities - a campaign aiming to help people get the most out of the system."