Stereotactic radiosurgery without whole-brain radiation therapy improved survival for patients with brain metastases from small cell lung cancer, according to study results.
“One of the historic reservations regarding the use of stereotactic radiosurgery in small cell lung cancer has been the concern that, by omitting whole-brain radiation therapy, a patient could be at a higher risk [for] a diffuse progression of brain metastases, and that this could negatively affect prognosis,” Chad Rusthoven, MD, assistant professor of radiation oncology at University of Colorado Cancer Center, said in a press release. “This study begins to address that concern by showing encouraging survival outcomes with stereotactic radiosurgery alone.”
The researchers used the National Cancer Database to identify 5,952 patients with small cell lung cancer and brain metastasis at diagnosis.
Rusthoven and colleagues stratified the patients by use of stereotactic radiosurgery or radiosurgery plus whole-brain radiation therapy. They used multivariate Cox regression and propensity score matching to determine each treatment’s effect on OS.
Median follow-up was 40 months. Two hundred patients received only stereotactic radiosurgery, whereas 5,752 underwent both radiosurgery and whole-brain radiation therapy.
Stereotactic radiosurgery appeared associated with longer median OS than radiosurgery plus whole-brain radiation therapy (10.8 months vs. 7.1 months; HR = 0.65; 95% CI, 0.55-0.75).
This improvement persisted in a multivariate analysis that controlled for extracranial metastases, comorbidities, race/ethnicity, age and sex (HR = 0.7; 95% CI, 0.6-0.81). Propensity score matching confirmed the OS benefit.
“Even though we only identified 200 patients with stereotactic radiosurgery, to the best of our knowledge, it’s the largest data set of patients treated this way and one of the first dedicated analyses of the approach in the United States,” researcher Tyler Robin, MD, PhD, resident physician of radiation oncology at University of Colorado, said in the press release. “The study offers preliminary evidence to support further research into the role of stereotactic radiosurgery for patients with small cell lung cancer.” – by Andy Polhamus
Disclosures: Rusthoven reports no relevant financial disclosures. One researcher reports a grant from Varian Medical Systems and a patent pending for automated tracking of fiducial marker clusters in X-ray images, both of which are outside of the submitted work.