Modern treatments have significantly boosted the 15-year survival rate for breast cancer, researchers say.

A scientific study has found that modern drug and hormonal therapies effectively cure many women rather than simply delaying the recurrence of disease reports The Lancet.

The Early Breast Cancer Trialists’ Collaborative Group studied at 145,000 cases, and found that surgery, alone or in combination with radiotherapy, can be used to remove all apparent traces of breast cancer if the disease is picked up at an early stage.

More than a million women worldwide each year are diagnosed with breast cancer. Surgery will remove the cancer and radiotherapy is given to kill any residual cells in the breast.

Chemotherapy and tamoxifen, a hormone therapy for oestrogen-sensitive cancers, are often recommended as extra treatment if appropriate, to stop the disease coming back.

Undetected cancer cell deposits may remain, and these can trigger a recurrence of disease, the use of drugs such as tamoxifen can prevent this recurrence by destroying these hidden deposits.

There has been some arguement whether women should be subjected to these extra treatments, as they are often associated with unpleasant side effects, but the evidence is that they help to improve survival rates at five years, the new study examined data on 145,000 breast cancer patients to determine their impact in the longer term.

The results showed that the appropriate use of treatments in combination approximately halved the 15-year risk of death from breast cancer for a middle-aged woman with hormone-sensitive disease. single treatment methods also proved to be effective by increasing survival rates by up to a third.

It did not include new treatments such as aromatase inhibitors, which studies have shown may be more effective than tamoxifen, or drugs such as taxanes.

The charity Cancer Research UK, say that this the largest follow-up study ever done in women with early breast cancer shows that great progress is being made in treating breast cancer effectively.

Breakthrough Breast Cancer, say that it is extremely reassuring to see evidence that established treatments are helping more and more women with early breast cancer live longer

They go on to say that to maintain the improvements, it is vital that there is greater investment in research.

In a commentary on the analysis, Karen Gelmon of the British Columbia Cancer Agency in Vancouver, Canada described the findings as impressive.

She said the survival curves suggest that the therapies could cure a proportion of women with early-stage breast cancer, rather than simply delay recurrence of the disease.