Intracranial Control and Radiation Sparing in ROS1-Positive NSCLC

Wade Iams, MD, frames central nervous system management around radiation sparing. Patients now live for years, and radiation toxicity often appears late, sometimes as necrosis, so delaying brain radiation through first and second line becomes a goal in itself; for an asymptomatic brain metastasis Iams considers short-interval magnetic resonance imaging a reasonable alternative when intracranial response rates support it. Martin Dietrich, MD, PhD, says intracranial response also signals coverage of micrometastatic disease, and that the risk of brain metastases rises in the second line, where the brain is often the site of progression. He notes circulating tumor DNA does not reflect intracranial biology and brain tissue is rarely obtainable, so he reimages at four to six weeks. Ticiana Leal, MD, adds that few patients in the pretreated trials had received the newest frontline agents.