Combining radiation and medication for breast cancer spread to the brain

This trial is testing a combination of three medications—tucatinib, trastuzumab, and capecitabine—along with radiation therapy (XRT) for people with HER2-positive metastatic breast cancer that has spread to the brain or spinal cord, a serious condition called leptomeningeal disease. The study wants to see if using this combination of radiation and the medication together is safe and effective at helping people live longer.

When breast cancer spreads to the brain or spinal cord membranes, patients typically survive only 2 to 4 months with current treatments. Past research suggests that combining radiation therapy with chemotherapy may help people survive longer than either treatment alone, so researchers want to test whether adding these specific medications makes this approach even more effective.