A new genetic test may allow breast cancer patients to find out whether they will respond positively to chemotherapy treatment. The study, appearing in the Journal of Translational Medicine, details how researchers analyzed the genes expressed in the tumors of eighty-three patients with primary breast cancer.
The study found that the researchers were able to predict which breast tumors would improve from chemotherapy in all cases of partial remission and nearly three quarters of the cases of complete remission. The researchers said that the ability to predict which patients will respond to chemotherapy, and which would not, would be a "powerful tool" in the treatment of breast cancer.
The researchers, led by Olga Modlich, were able to identify a total of fifty-seven 'predictor' genes active in tumors: thirty-one genes associated with a favorable response and twenty-six genes associated with a poor response. The authors then tested the ability of these genes to predict the response of twenty-seven breast cancer patients, who were then treated with preoperative systemic chemotherapy.
The predictor genes could be used to correctly predict the outcome of preoperative systemic chemotherapy in all cases of partial remission and nearly 75 percent of cases of complete remission of primary tumors. According to the researchers, the use of micro-array technology to identify genes that can predict response to chemotherapy could represent a powerful tool to identify patients for whom preoperative systemic chemotherapy would be the most successful form of treatment.
At the present time, decisions about whether to use chemotherapy as a breast cancer treatment are based on factors such as the patients' age and type and size of tumor. But these factors do not provide sufficient information to tailor treatment to the individual patient which means nearly all breast cancer patients receive standard chemotherapy treatment. The researchers said that "the identification of molecular markers predictive of patients' responsiveness to treatment is becoming a central focus of research." The ability to predict a patient's response to chemotherapy for breast cancer would be of benefit to doctors and patients, shifting the focus away from a standard treatment for all patients and towards custom treatments based on the patients' genetic make-up.
