Effect of immunotherapy and stereotactic radiosurgery on cognitive function and quality of life in long term survivors of metastatic brain malignancies.

125 Background: Use of whole brain radiation, radiosurgery, targeted therapies, and more recently, immunotherapies have resulted in improved survival for patients with brain metastases. As patients live longer, it is becoming increasingly important to understand the long-term cognitive function (CF) and quality of life (QOL) changes associated with these therapies. Methods: The Yale Gamma Knife Database was searched for patients surviving greater than 2 years after brain metastasis diagnosis. Of 79 patients identified, 19 were willing to participate in study. All participants underwent a single assessment session of cognitive tests that evaluated executive function (TMTa and TMTb), processing speed (COWA), memory (HVLT), and quality of life (FACT-Br). Results: Within the whole group, mean age was 65.5 years (range 50-88), median time from brain metastasis diagnosis to testing was 60 months (range 25.6-120.6). Mean number of lesions treated was 3.8 (range 1-10). Mean total lesion volume treated was 14.1 mm3 (range 0.6 - 39). Only 2 patients were treated with whole brain radiation therapy. Patient scores were compared to validated normative data for their age group. Patients performed worse than normal for their age on TMTb (p < 0.0001), total word recall (p < 0.0001) and discriminative ability (p = 0.0004). Patients performed as expected for age on TMTa, animal naming, FAS, and % retention. A negative correlation was seen between executive function results and QOL (TMTa: r = -0.569, p ≤ 0.05, TMTb: r = -0.484, p ≤ 0.05) and a positive correlation was seen between processing speed results and QOL (r = 0.672, p ≤ 0.001). Conclusions: In patients surviving more than 2 years after diagnosis and successful treatment of brain metastases, this study shows that portions of executive function and memory are worse than expected for their age, while cognitive processing speed is similar to norms. Cognitive function was correlated with QOL; patients with lowered cognitive function reported a lower quality of life. Given this preliminary data, a further study in a larger population is needed to determine if certain treatments preferentially predispose patients to declines in CF and QOL.