Taking hormonal drugs for up to 15 years reduces the risk of breast cancers coming back, a landmark study suggests.
The trial, involving 1,918 patients, which had top billing at the world’s largest cancer conference, showed the risk was cut by a third.
Experts described it as a “big deal” that will change treatment for millions of women.
But they warned there were risks, including osteoporosis.
Globally, 1.7 million women are diagnosed with breast cancer around the world each year.
Around 80% of the tumours are fuelled by the female sex hormone, oestrogen.
Such cancers have a low but persistent risk of returning that lasts for years.
It is why women already take drugs such as tamoxifen, to prevent oestrogen getting into breast cells, or aromatase inhibitors, which stop the body making oestrogen, for years after the lump is removed.
The trial, carried out on post-menopausal women, doubled aromatase inhibitor treatment from five to 10 years.
The data, presented to the American Society of Clinical Oncology (ASCO), showed that cancer recurrence was cut by 34%.
But many women on the trial had already taken other hormonal drugs before starting on aromatase inhibitors and benefited from 15 years of treatment. Read Full Story