A 55-year-old man is evaluated in the hospital for an episode of painful tingling in the right arm followed by clonic jerking of that arm lasting 3 minutes. Medical history is significant for non–small cell lung cancer diagnosed 1 year ago and treated with surgical resection. He was evaluated in the emergency department 1 week ago for a new-onset headache, at which time an isolated brain metastasis in the left parietal area was identified. He subsequently was admitted for planned surgical resection of this lesion, adjuvant local radiation, and systemic chemotherapy.
On physical examination, temperature is 36.6 °C (97.9 °F), blood pressure is 120/92 mm Hg, pulse rate is 105/min, and respiration rate is 16/min. Right inferior quadrantanopia, right neglect, increased tone in the right arm and leg, and a plantar extensor response in the right toe are noted.
An MRI of the brain shows a stable contrast-enhancing lesion in the left parietal lobe consistent with the patient's known metastasis.
An electroencephalogram shows left hemispheric slowing with no evidence of epileptiform discharges.
Which of the following is the most appropriate management?