Could patients benefit from whole-brain radiotherapy with unilateral hippocampus sparing?

Evidence that the hippocampus plays an important role in advanced neuro-cognitive functions (NCF), including the formation of new memories, has accumulated since the 1950s [1]. Reports describing bilateral lesions in the hippocampus that developed clinically detectable neurological impairments suggest that bilateral damage of this structure have negative effects [2–3]. Recently, the randomized NRG-CC001 study [4] provided additional evidence that this structure is related to the memory functions of the brain. The authors found that in the setting of whole brain irradiation (WBRT) with memantine, lowering the bilateral hippocampal radiation dose preserved NCF and patient-reported symptoms. Importantly, relapses in the hippocampus avoidance (HA) region did not increase — occurring in 11 of 257 patients in the HA-WBRT plus memantine arm versus 16 of 261 in the WBRT plus memantine arm. © 2021. Reports of Practical Oncology and Radiotherapy.All Rights Reserved