A lack of awareness of breast cancer symptoms among older women could be to blame for the fact they are more likely to be diagnosed at a later stage, research suggests.
Compared to women aged 65 to 69, those aged 70 to 74 have a 21% higher chance of being diagnosed with late stage breast cancer, according to the study in the British Journal of Cancer.
The risks get even higher with advancing age, with those aged 75 to 79 having a 46% higher chance of a late-stage diagnosis.
These findings held true even when experts took account of breast screening among the women. Late stage diagnosis was more common in women from deprived backgrounds.
Friday's research also found that the chance of being diagnosed with advanced lung cancer actually falls with advancing age.
Compared to those aged 65 to 69, people aged 70 to 74 were 18% less likely of be diagnosed with late stage lung cancer.
For those who were older, aged 75 to 79, the chance was 26% lower.
The research, carried out by experts at the University of Cambridge and the Eastern Cancer Registration and Information Centre (ECRIC), included around 17,800 women with breast cancer and more than 13,200 patients with lung cancer in the east of England diagnosed between 2006 and 2009.
Dr Georgios Lyratzopoulos, study author based at the University of Cambridge, said: "Patient awareness of the signs of breast cancer is known to be lower among older women and this may explain why breast cancer is diagnosed later among this age group.
"But it is puzzling why older patients have a lower risk of advanced stage lung cancer. More research is needed to better understand this pattern."
Sara Hiom, director of information at Cancer Research UK, said: "If cancer is caught early, patients have a better chance of beating the disease as more effective treatment options are available.
"We have made great progress in improving cancer survival rates in the last 40 years, but there is still more work to be done to help more people survive cancer.
"Collecting information on stage at diagnosis is vital to do this and we must think how to target messages appropriately to the right audiences.
"Cancer Research UK works to raise symptom awareness, and encourage and enable people to go visit their doctor as soon as their notice anything unusual for their bodies."