Patients Regain Cognitive Function After Radiation for Brain Tumors
Radiation for Brain Tumors
Patients who suffer from low-grade brain tumors are able to regain normal cognitive function after receiving radiation therapy to shrink their tumor, according to a study published in the November 15, 2005, issue of the International Journal of Radiation Oncology*Biology*Physics, the official journal of ASTRO, the American Society for Therapeutic Radiology and Oncology.
Prior to undergoing radiation therapy to treat their brain tumor, the 20 patients studied were submitted to a battery of intensive cognitive tests measuring intelligence, memory, learning and attention span to establish a baseline score to compare to future results. Following radiation therapy, patients were re-evaluated at 18-month intervals over the next five years. While the baseline test results were considered below average compared to age-specific norms, the first test after receiving radiation showed an increase in the group's overall score.
"These results suggest that the patients with brain tumors perform below average on these tests before radiation therapy because the tumor itself affects their cognitive skills," said Paul D. Brown, M.D., co-author of the study and a radiation oncologist at the Mayo Clinic in Rochester, Minn. "After the radiation, the brain function of the patients in the study went back to their normal, pre-tumor levels and stayed there for five years. This shows that a moderate dose of radiation, using modern techniques, does not cause cognitive injury in brain tumor patients."
Of the 20 patients, only one patient reverted back to their baseline scores three years after radiation therapy and across the board improvement was noted in immediate verbal memory, learning, long-term verbal memory, cognitive flexibility and spatial problem solving.
"Average life expectancy for these patients is three to 10 years and because there are no curative treatments for this type of cancer, a high priority is given to maintaining cognitive function and hence quality of life for as long as possible," said Brown. "This study shows that we can maintain and even improve the quality of life for someone suffering from a brain tumor."