Elevated hormones increase breast cancer risk

Increased hormone levels can contribute to a higher risk of breast cancer, scientists have found.

In a study from the Brigham and Women's Hospital and Harvard Medical School, and published by journal Breast Cancer Research, it was noted that high levels of hormones such as oestrogen or testosterone are known to have a higher risk of breast cancer in post-menopausal women.

However, the team looked at eight different sex and growth hormones and determined that each elevated hormone increased the risk of breast cancer further, with every additional hormone increase raising the risk by 16 per cent.

High levels of circulating oestrogens (oestrone and oestrogen), prolactin, and androgens (testosterone, androstenedione, DHEA, or DHEA-sulfate) were also each linked with an in breast cancer risk of between 50 and 200 per cent.

"Our results suggest that models used to assess breast cancer risk could be improved by taking into account multiple sex hormone and growth hormone levels," said Dr Shelley Tworoger, from Brigham and Women's Hospital.

Meanwhile, a team from the Cleveland Clinic also found that a gene known as an androgen receptor (AR) was found to increase breast cancer growth when 'turned off'.

Posted by Fiona Griffiths