WOMEN whose breasts are not of equal size and shape are more likely to develop cancer, according to a new study.
Researchers examined the breast X-rays, known as mammograms, of more than 500 women, half of whom went on to develop breast cancer and half who did not. They found that the women who suffered cancer had less-symmetrical breasts than those who were disease-free.
The team, from the University of Liverpool, said breast symmetry may be an important indicator of a woman's risk of breast cancer.
Dr Diane Scutt, the director of research at Liverpool University's School of Health Sciences, examined the difference in volume between the left and right breasts, measured and calculated from mammograms.
The researchers, writing in the journal Breast Cancer Research, also took into account factors such as a family history of the disease to calculate women's risk of developing cancer.
They found that women who went on to get cancer were more likely to have greater difference between their breasts.
The chances of developing breast cancer increased by 50 per cent for every 100ml increase in the difference.
Dr Scutt said that perfect symmetry may be disturbed by factors such as hormones like oestrogen, which is known to affect the development of breast cancer.
However Maria Leadbeater, a nurse specialist with the charity Breast Cancer Care, cautioned: "There are many causes of breast asymmetry, and for many women having slightly different-shaped breasts is perfectly normal."