Prospective memory impairment following whole brain radiotherapy in patients with metastatic brain cancer

Objective To investigate the prospective memory ( PM ) impairment following whole brain radiotherapy ( WBRT ) in cancer patients with brain metastases. Method Eighty‐one patients with metastatic brain cancer, agreeing to undergo WBRT , were enrolled and subjected to a battery of cognitive neuropsychological tests, including the mini‐mental state examination ( MMSE ), verbal fluency test ( VFT ), digit span test ( DST ), and event‐based and time‐based prospective memory ( EBPM and TBPM ) tasks, before and after radiotherapy. Results The patients with metastatic brain cancer after WBRT exhibited a significant decrease in the MMSE , DST , VFT , and EBPM scores ( t  = 6.258, 10.192, 5.361, −5.892, P  <   0.01), but nonsignificant decrease in the TBPM scores ( t  = −1.172, P  >   0.05). Conclusion There is significant EBPM impairment in cancer patients with brain metastases after WBRT , whereas that in the TBPM remained relatively unaffected. The result suggests that EBPM impairment may be as an early cognitive impairment marker in patients with BM who undergo WBRT .