Addition of whole-brain radiation therapy for brain tumor treatment led to cognitive decline

Patients who received whole-brain radiation therapy in addition to stereotactic radiosurgery for treatment of brain tumors demonstrated a significant decline in learning and memory function at four months after treatment compared with patients who received stereotactic radiosurgery alone, according to recently published data.

The data monitoring committee stopped the trial short based on a 96% probability that patients receiving the combination treatment experienced declines in learning and memory.

Between Jan. 2, 2001, and Sept. 14, 2007, researchers randomly assigned 58 patients with one to three newly diagnosed brain metastases to stereotactic radiosurgery and whole-brain radiation therapy (n=28) or to stereotactic radiosurgery alone (n=30). Neurocognitive function was assessed using the Hopkins Verbal Learning Test-Revised total recall. Significant deterioration was considered a five-point drop from the baseline score.

After four months, 64% of patients assessed in the whole-brain radiation therapy and stereotactic radiosurgery group had deteriorated compared with 20% of patients in the stereotactic radiosurgery alone group. The researchers reported a 52% mean posterior probability of decline in learning and memory function for those patients assigned to whole-brain radiation therapy and stereotactic radiosurgery compared with a 24% mean posterior probability of decline for patients assigned to stereotactic radiosurgery only.

This finding remained at six months — mean posterior probability of decline was 28% for the combined treatment group compared with 8% for the stereotactic radiosurgery alone group. At four months, results of the delayed recall and delayed recognition portions of the Hopkins Verbal Learning Test also suggested a high probability of decline in patients receiving both treatments.

Also at four months, four deaths occurred in the stereotactic radiosurgery alone group, and eight occurred in the combined treatment group. At one year, in the combined group, 73% of patients were free from central nervous system recurrence compared with 27% of patients who received stereotactic radiosurgery alone (P=.0003).

The researchers recommended initial treatment with a combination of stereotactic radiosurgery and close clinical monitoring to ensure preservation of learning and memory in these patients.

Chang EL. Lancet Oncol. 2009;doi:10.1016/S1470-2045(09)70263-3.