Neurocognitive functioning after Gamma Knife and LINAC stereotactic radiosurgery in patients with brain metastases.

Abstract

Brain metastases (BM) themselves and treatment with stereotactic radiosurgery (SRS) can influence neurocognitive functioning. This prospective study aimed to assess neurocognitive decline in patients with BM after SRS. A neuropsychological test battery was assessed yielding ten test outcomes. Neurocognitive decline at 3 and 6months post SRS was compared to measurement prior to Gamma Knife (GK) or linear accelerator (LINAC) SRS. Reliable change indices with correction for practice effects were calculated to determine the percentage of neurocognitive decline (defined as decline on ≥ 2 test outcomes). Risk factors of neurocognitive decline were analyzed with binary logistic regression. Of 194 patients pre-SRS, 40 GK and 29 LINAC patients had data accessible at 6months. Compared to baseline, 38% of GK patients declined at 3months, and 23% declined at 6months. GK patients declined on attention, executive functioning, verbal memory, and fine motor skill. Of LINAC patients, 10% declined at 3months, and 24% at 6months. LINAC patients declined on executive functioning, verbal memory, and fine motor skills. Risk factors of neurocognitive decline at 3months were high age, low education level and type of SRS (GK or LINAC). At 6months, high age was a risk factor. Karnofsky Performance Scale, BM volume, number of BM, tumor progression and neurocognitive impairment pre-SRS were no risk factors. Neurocognitive decline occurs in a considerable proportion of patients with BM treated with GK or LINAC SRS. Overall, high age appears to be a risk factor for neurocognitive decline after SRS.