About 10 percent of lung cancers in the United States and as many as 40 percent in Asia are driven by mutations in the EGFR gene. EGFR targeted treatment advances over the previous decade now result in multiple options for controlling the disease in the body, but due to the reduced ability of many of these drugs to penetrate into the brain, treatment of disease in the brain remains challenging. When brain metastases are seen at diagnosis before a patient has tried EGFR-targeted drugs, it has been an open question whether doctors should try drugs alone just in case they work in the brain or move directly to whole-brain radiotherapy or stereotactic radiosurgery (a tightly focused form of radiation) first, followed by targeted medicines. A study published in the Journal of Clinical Oncology looks back at 351 patients with EGFR mutant lung cancer and brain metastases treated at six institutions to offer compelling preliminary evidence as to the best sequence of these techniques: Radiation followed by targeted medicines resulted in the longest overall survival.
“This particular study illustrates a remarkable finding and raises an interesting question. First of all, these patients all had tumors that had spread to the brain. Before we had these EGFR-directed medicines, their average survival would have been less than a year. But for patients treated with the newer medications, even if the cancer has spread to the brain, we are seeing survival ranging from 2-4 years on average, and that is a sign of fantastic progress for at least some lung cancer patients,” says Brian Kavanagh, MD, MPH, FASTRO, professor and chair of Radiation Oncology at the University of Colorado Cancer Center, and President of the American Society for Radiation Oncology (ASTRO).