A nationwide collaboration between breast cancer experts that was established just six months ago has already delivered important findings about the resistance of some cancers to a commonly used drug.

BREAST-PREDICT is a country-wide collaboration involving over 50 experts in the field of breast cancer research. Central to this research is the development of a national breast cancer biobank and database, which includes patient information, tumour tissue and blood samples collected from almost every breast cancer patient in the country.

Having this data allows researchers to improve their understanding of the disease, with an overall aim of delivering more personalised treatment to each patient.

The researchers have already made an important discovery in relation to the commonly used breast cancer drug, Herceptin.

Patients who test positive for high levels of a particular protein - Her2 - are usually treated with this drug. However, the researchers have found that many patients with high levels of Her2, who also have tumours that test positive for the oestrogen receptor, are more likely to develop resistance to this drug.

Some 70% of all breast cancers are oestrogen receptor positive.

It is hoped this discovery will help scientists to identify in advance patients who are unlikely to respond to Herceptin and who may need alternative treatment.

Meanwhile, according to the researchers, while oestrogen receptor positive breast cancers are very treatable and usually have an excellent prognosis, some patients become resistant over time to common treatments. This can lead to a recurrence of the primary tumour. In some cases, the cancer can spread and death results.

BREAST-PREDICT has found that if a patient's tumour expresses a protein called PRDX1, they are more likely to develop a recurrence of the disease. This could have implications for the treatment of these patients in the future.

Commenting on BREAST-PREDICT's first six months in operation, the research programme's lead, Prof William Gallagher, of University College Dublin, said that ‘great strides' had been made, ‘with initial findings coming through now that are actually making an impact on the way in which we treat breast cancer'.

"Every cancer is different. Personalised medicine, which takes into account the exact type of tumour, will be what delivers better outcomes for patients in the future," he said.

BREAST-PREDICT will run for a five-year period, with an investment of €7.5 million from the Irish Cancer Society.