A year of treatment with a medicine made of an antibody and chemotherapy drug has proven highly effective in preventing stage 1 HER2-positive breast cancer from recurring in patients, a team led by Dana-Farber Cancer Institute researchers has found. In a clinical trial involving 512 patients with the earliest stage of breast cancer that tested positive for the HER2 protein, 97% of those treated with trastuzumab emtansine (T-DM1) after surgery were alive and free of invasive cancer five years after treatment. The results, published online today in the Journal of Clinical Oncology , suggest that T-DM1 is a reasonable treatment approach for this stage 1 population, the study authors say.
In conjunction with the trial, researchers looked for biomarkers of whether the cancer was likely to recur even after treatment with T-DM1. They found that patients with high scores on the HER2DX test – which weighs clinical factors and the activity of four genes within tumor tissue – had a greater risk of recurrence. "Patients with stage 1 HER2-positive breast cancer have recurrence rates of 5 to 30%.
Post-surgical treatment with chemotherapy and the antibody trastuzumab, which binds to HER2, can significantly reduce the risk of recurrence in these patients. But the side effects can have a detrimental impact on patients' quality of life," says study lead author Paolo Tarantino, MD, of Dana-Farber and the University of Milan (Italy). In this study, we evaluated T-DM1, which links trastuzumab.
