PhD student, Britta Weigelt told the meeting of the 4th European Breast Cancer Conference today (Thursday 18 March) that, contrary to what had been thought previously, any primary breast cancer cell was capable of producing secondary cancer cells, which then spread to other parts of the body. These secondary cancer cells had a strikingly similar genetic make-up to their parent cells and behaved in a similar way. Therefore, metastases were likely to have the same response to a particular treatment as their primary tumour.
The discovery has implications for the treatment of breast cancer once researchers have identified the ways that genetically different tumours respond to a variety of therapies. Based on the genetic profile of a patient's tumour, doctors could choose the best treatment for that particular type of tumour (from specific types of chemo-, radio- or hormonal therapies) and treat the patient with it from the time of diagnosis. Such early (neo-adjuvant) treatment could not only shrink the primary tumour but might also prevent the outgrowth of micrometastases, thereby saving lives, as metastases that occur in other parts of the body are notoriously difficult to treat successfully and are the main cause of death in breast cancer.
Mrs Weigelt said: "Until now it was largely unknown whether the characteristics of breast cancer that define the growth rate and therapy response of the primary tumour were alike in the metastases. Furthermore, it was unclear whether all primary breast cancer cells were capable of metastasising, or only some of them."
In the first study to do this, Mrs Weigelt and her colleagues at the Netherlands Cancer Institute in Amsterdam compared the activities of genes in samples of primary breast tumours from 15 patients and in their matching lymph
Contact: Emma Mason
Federation of European Cancer Societies