More than a third of women in London who are eligible for breast cancer screenings fail to attend appointments, a report has revealed.
One in nine women will be diagnosed with the disease
Behind the Screen, a London Assembly report, also shows that poorer women are less likely to go to screenings.
Although older women in more affluent areas are most at risk of developing breast cancer, survival rates are lower in deprived areas.
In 2005, 1,185 people from London died of breast cancer.
One in nine women will be diagnosed with the disease during their lifetime.
The risk increases as women get older, with 80% of cases occurring in women over 50. Woman aged 50 to 70 are invited to attend screenings.
However, a government report released last year showed that only 64% of women invited to mammogram appointments in London attended, compared to the national average of 75%.
The investigation by the assembly's health committee showed Havering and Bexley had the highest uptake, while Westminster, Kensington & Chelsea, and Tower Hamlets had the lowest.
"There are still low levels of awareness of the screening programme, breast cancer symptoms and risks amongst certain groups, particularly black, Asian and minority ethnic women," a spokesperson said.
The report also said long waiting times for treatment increased stress for patients.
Breast cancer patients should start treatment within four weeks of surgery, but in more than a third of London's acute trusts waiting times were longer.
Committee chairwoman Joanne McCartney said: "Early diagnosis is crucial to survival, which is why our report puts forward a number of ways to improve the screening rates in the capital and to make women more aware of the symptoms and risks of breast cancer."
Improvements recommended by the report include bringing London's five cancer networks together to coordinate radiotherapy treatment services to cut waiting times.
Publicity campaigns to raise awareness about screenings to vulnerable woman could also be introduced.