A recent study conducted at NYU Langone Health, published in the Journal of Neurosurgery, has revealed that the rate of new brain metastases from non-small cell lung cancer (NSCLC) in patients off systemic therapy decreases over time and is uncommon two years after discontinuation of systemic cancer therapy.

In addition, the researchers found that patients who had RAS or receptor tyrosine kinase (RTK) pathway mutations or who stopped treatment due to adverse events had a higher rate of developing new metastases.

The findings surprised the research team, led by Dennis London, MD, a resident in neurosurgery at NYU Langone.

“Patients who discontinued therapy due to a treatment response had a median time to new brain metastases of 16 months—much longer than we expected,” says Dr. London.

He further explained that these data suggest that the RAS pathway is an aggressive driver of brain metastases in NSCLC, but additional studies with larger sample sizes will be needed to validate this hypothesis.

Based on these findings, Dr. London recommended that oncologists use caution when choosing to discontinue therapy in patients with RAS pathway mutations.

“These data are very encouraging for lung cancer patients with brain metastases,” Dr. London explains. “Achieving long-term neurological control of brain metastases is possible after treatment with new systemic therapies.”
“This is the first study to report the incidence of new brain tumors for patients who can stop their cancer therapy,” says Douglas Kondziolka, MD, a professor of neurosurgery and radiation oncology. “The good news is that for some patients, over years of assessment, new brain tumors were uncommon.”