Forefront Magazine | Volume 5, Issue 4, 2016
Mayo Clinic Forefront magazine: Shift in practice may reserve whole-brain radiation for patients with extensive disease.
Paul D. Brown, M.D.
Patients with three or fewer metastatic brain tumors who received treatment with stereotactic radiosurgery (SRS) had less cognitive deterioration three months after treatment than did patients who received SRS combined with whole-brain radiation therapy.
This finding is among the results of a federally funded Mayo Clinic-led multi-institution study whose results were published in the July 26, 2016, issue of JAMA.
"Metastatic brain tumors are, unfortunately, common in patients with cancer," said Paul D. Brown, M.D., a radiation oncologist at Mayo Clinic in Rochester, Minnesota, and lead author of the published study.
While stereotactic radiosurgery gives physicians the opportunity to treat tumors and spare healthy brain tissue, a combination of SRS and whole-brain radiation therapy (WBRT) has been shown to help control growth of metastatic brain tumors.
"The concern is that WBRT also damages cognitive function," Dr. Brown said. "That is why we have been studying the use of SRS alone."
Researchers enrolled 213 patients between February 2002 and December 2013, and randomly assigned them to treatment with stereotactic radiosurgery alone (111) or stereotactic radiosurgery followed by whole-brain radiation therapy (102).
Researchers found less cognitive deterioration at three months in patients treated with SRS alone. Quality of life was also higher at three months among patients treated with SRS alone.
There was no significant difference in functional independence at three months between the two treatment groups. Median overall survival was 10.4 months for patients treated with SRS alone and 7.4 months for patients treated with SRS and WBRT.
"This is the first large-scale clinical trial to evaluate this patient population with a comprehensive battery of cognitive and quality-of-life instruments," Dr. Brown said. "WBRT has often been offered early in the disease course for patients with metastatic brain tumors. But because of this trial, we know the negative impact of WBRT on both quality of life and cognitive function is significant. With these trial findings, we expect practice will shift, reserving WBRT for patients with more extensive disease in the brain."