New Study on Breast Cancer

Protein test predicts invasive breast cancer

* 27 April 2008
* From New Scientist Print Edition. Subscribe and get 4 free issues.

Thousands of women could be spared surgery for breast cancer with a test that can predict the likelihood of developing an invasive tumour.

Thea Tlsty and colleagues at the University of California, San Francisco, analysed breast tissue from 70 women who had been diagnosed with a breast-cancer precursor called ductal carcinoma in situ. They looked for abnormal expression of the proteins p16 and ki67, which are linked to tumour growth and cell proliferation, and also for the enzyme Cox-2.

Women with high levels of either p16 or Cox-2, combined with high levels of ki67, had a very high probability of developing invasive breast cancer. If ki67 was absent, however, high levels of p16 and Cox-2 indicated a very low risk.

As less than 25 per cent of women diagnosed with DCIS go on to develop an invasive tumour, those identified as high risk could be given aggressive treatment, says Tlsty, while those at low risk could be spared unnecessary surgery and drugs (Cancer Cell, DOI: 10.1016/j.ccr.2007.10.017).