On the horizon: two new breast cancer tests

A new test could enable doctors to more accurately predict if women are at a higher risk of carrying a mutated BRCA1 breast cancer gene. This may help women who do not know if the disease runs in their family decide whether they need to be tested for the mutated gene. The current criteria for referral for this testing includes knowledge of a strong family history of breast or ovarian cancer.

People carrying a faulty version of the BRCA1 gene have an 80 per cent chance of developing cancer in the breast or ovary, a 50 per cent chance of developing a second breast cancer and a 40 per cent chance of developing a second cancer in the ovary. Faults in the BRCA1 and BRCA2 genes increase the risk of developing cancer because both normally protect the cells from cancer-causing changes. However, fewer than five per cent of all breast cancers are due to BRCA1 and BRCA2 gene mutations.

In the latest study, scientists from Cancer Research UK in Cambridge, Leeds and Manchester, along with others from around the world tested 200 breast tumours for a specific marker. They found that 56 per cent of all BRCA1 gene mutation carriers tested positive for this marker.

'Many women who don't know their family history of breast cancer can be anxious about their children's risk when diagnosed. We hope that this novel marker test can be further developed to identify more patients in the future who should consider genetic testing but who do not fit the current criteria', said Professor Doug Easton from Cancer Research UK's genetic epidemiology unit in Cambridge.

Meanwhile in Germany, researchers may have found a way to tell whether a breast cancer patient will respond positively to pre-operative systemic chemotherapy (PST).

Researchers led by Olga Modlich at the University of Dusseldorf and Bayer HealthCare AG found 57 'predictor' genes by analysing samples of breast tissue from five healthy people and 56 breast cancer patients by DNA microarray analysis. Thirty-one of the 'predictor' genes are associated with a positive response to PST and 26 are associated with a poor response.

The genes were then used to predict the outcome of PST in 27 patients. They correctly predicted the outcome of the treatment in all cases of partial remission and 75 per cent of cases in complete remission of primary tumours.

If this test is further developed, it could be an important resource to help doctors identify which drugs will be the most appropriate for which patients.