Oncologists now know where to look to identify breast cancer, according to a Washington University study. Using a set of just 50 genes, they can reliably identify the four known types of breast cancer and potentially predict the best therapy treatment for each tumor type.
Although the cancer types are distinguished by thousands of genetic differences, the researchers were able to narrow the list down to a set of 50 of these genes that could uniquely identify each of four types.
The researchers also compared the activity of the gene set to how well 133 breast cancer patients responded to standard chemotherapy. They found that their genetic test was highly sensitive and very predictive for chemotherapy response. The test was more predictive than typically used clinical molecular markers such as estrogen receptor status.
The researchers plan to study tumor samples from breast cancer cases going back a decade or more. Since the patients in these cases have already been treated, the researchers can relatively quickly discover how well various therapies worked for each breast cancer type.