CHICAGO–Initial treatment with radiosurgery (SRS) and close monitoring is recommended to better preserve cognitive function in patients with newly diagnosed patients with one to three brain metastases who are eligible to receive SRS, data presented at the 2015 American Society of Clinical Oncology (ASCO) 2015 annual meeting has shown.
“In the United States alone, approximately 400,000 patients per year are diagnosed with brian metastases,” said Paul D. Brown, MD, principal investigator and radiation oncologist at the University of Texas MD Anderson Cancer Center in Houston, TX. “Radiosurgery is an effective treatment for brain mets; however, radiosurgery alone results in a high rate of development of new brain mets and a significant proportion have progression of the treated lesions.”
Despite a significant improvement in intracranial control with whole brain radiation therapy (WBRT), there is no improvement in survival and there are concerns over neurocognitive decline after WBRT.
For the phase 3 trial, researchers enrolled 213 patients with newly diagnosed brain metastases. Of those, 208 were randomly assigned to receive SRS alone or SRS plus WBRT. All patients underwent cognitive testing prior to and following treatment. “Dose of radiosurgery was determined by size of the lesions,” Dr. Brown added. “Baseline characteristics were well-distributed among both study arms.”
Most patients’ primary cancer was of the lung (68%) and the median age of patients was 60 years.
Results showed that cognitive progression at 3 months occurred in 91.7% of those who received SRS and WBRT compared with 63.5% with SRS alone (P=0.0007). Cognitive progression persisted at 6 months in 77.8% and 97.9% with SRS alone and SRS and WBRT, respectively (P=0.032).
Furthermore, the WBRT plus SRS group experienced more deterioration in immediate recall (30.4% vs. 8.2%; P=0.0043), delayed recall (51.1% vs. 19.7%; P=0.0009), and verbal fluency (18.6% vs. 1.9%; P=0.0098) than the SRS alone group.
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Researchers found no statistically significant difference in median overall survival between the two groups (7.4 months for WBRT and SRS vs. 10.4 months for SRS alone; HR=1.02; 95% CI: 0.75,1.38; P=0.92).
Ultimately, adjuvant WBRT improved brain control, had no impact on overall survival, and worsened overall quality of life and functional well-being.
Dr. Brown concluded, “For patients with newly diagnosed brain metastases that are amenable to SRS, we recommend initial treatment with SRS alone and close monitoring to better preserve cognitive function and quality of life.”
- Brown PD, Asher AL, Ballman KV, et al. NCCTG N0574 (Alliance): A phase III randomized trial of whole brain radiation therapy (WBRT) in addition to radiosurgery (SRS) in patients with 1 to 3 brain metastases. J Clin Oncol. 2015;33:(suppl; abstr LBA4).