A link between vascular damage and cognitive deficits after whole-brain radiation therapy for cancer: A clue to other types of dementia?

Whole brain radiation therapy for the treatment of tumors can sometimes cause cognitive impairment. Memory deficits were noted in up to 50% of treated patients over a short period of several months. In addition, an increased rate of dementia in young patients has been noted over the longer term, i.e. years. A deficit in neurogenesis after irradiation has been postulated to be the main cause of cognitive decline in patients, but recent data on irradiation therapy for limited parts of the brain appear to indicate other possibilities. Irradiation can directly damage various types of cells other than neuronal stem cells. However, this paper will focus on injury to brain vasculature leading to cognitive decline since vessels represent a better therapeutic target for drug development than other cells in the brain because of the blood-brain barrier.