A patient with brain metastases who is treated with radiation therapy may develop cognitive problems if the patient survives long enough. A few patients may have a reversible impairment.
Clinical features:
(1) aggressive whole brain radiation therapy for brain metastases or focused radiation therapy for a solitary metastasis
(2) high daily radiation fractions (>= 300cGy)
(3) control of both intra and extra-cranial disease with prolonged survival
(4) delayed onset of progressive dementia, ataxia, and urinary incontinence with severe impairment
CNS damage may be enhanced by concurrent neurotoxic chemotherapy.
Imaging studies show morphological CNS changes which may include:
(1) cortical atrophy
(2) hypodense white matter
(3) areas of radionecrosis which appear as contrast-enhancing lesions
