Refining radiation techniques: Focus on hippocampal sparing WBRT

Whole brain radiotherapy (WBRT) has been considered the standard treatment in patients with multiple brain metastases. In patients with a limited number of brain metastases, the use of more aggressive treatment, including stereotactic radiosurgery with or without WBRT has been proposed. Moreover, technological improvement allows clinicians to deliver simultaneously WBRT and a boost dose to brain metastases. In the last decades, WBRT has been questioned due to the presumed late decline in neurocognitive functions (NCFs); moreover, several clinical trials found relationships between hippocampal deterioration and NCFs decline after WBRT. New clinical trials are evaluating the use of hippocampal avoidance in WBRT. Nevertheless, the benefit on NCFs deficit remains unclear. Aim of the review is to analyse the role of hippocampal avoidance, the impact of technology and the current clinical trials on going for hippocampal sparing radiotherapy. Abstract