Sharon Osborne double mastectomy: A background on preventative surgery

Preventative surgery for women at risk of breast cancer has been steadily increasing over the last 10 years – with experts saying it could cut the risk by up to 90 per cent.

It is thought around one in 800 women in the UK carry the defective BRCA1 gene, which leaves them with an 85 per cent risk of going on to develop breast cancer.

The presence of the defective gene, which is detectable by screening, also increases the risk of ovarian cancer to 60 per cent.

Preventative techniques such as mastectomies are considered to offer the highest survival rates of all pre-breast cancer treatments.

Women with the defective BRAC1 gene who undergo a preventative mastectomy are left with 90% lower risk of developing breast cancer – around half the risk of woman born without the BRAC1 defect.