P01.06.B EVOLUTION OF NEUROCOGNITIVE FUNCTIONING AFTER RADIOTHERAPY IN PATIENTS WITH BRAIN METASTASES

Abstract

Abstract BACKGROUND Brain metastases (BMs) occur in ten to thirty percent of the adult population. They present a heterogeneous population, with almost half already experiencing cognitive impairment prior to brain radiotherapy (RT). While RT aims to improve or stabilize the neurologic deficit(s), neurocognitive decline is often reported after treatment. To better understand cognitive performance after RT, we assessed the individual cognitive performance before, three months and at least eleven months after RT. METHODS The study population consisted of 32 adult patients with BMs that were referred for brain RT. An elaborate battery of neuropsychological tests was used to assess objective cognitive performance. Additionally, the Cognitive Failures Questionnaire (CFQ) and a semi-structured interview measured subjective cognitive performance and the EORTC QLQ-C30 and EQ-5D-3L were used to assess quality of life (QoL). The reliable change index (RCI) as formulated by Maassen et al. (2009) represented clinically significant change in cognitive performance at the follow-up time points, whereby RCI <-1.645 was denoted decline and RCI >1.645 improvement. This RCI takes into account test-retest reliability and practice effects. RESULTS Three months post-RT, 83% of the patients showed declines in at least one cognitive domain, with declines most frequent in memory (58%) and processing speed (36%). On the other hand, improvements were also found, especially for attention (92%) and fine motor coordination (46%). 50-60% of patients showed further decline in cognitive performance at task-level from three to eleven month follow-up, while 40% of patients showed further improvement. Multinomial logistic regressions indicated that a higher number of BMs was predictive of declined cognitive performance three months post-RT, specifically regarding executive functioning, processing speed and fine motor coordination. Additionally, patients without symptoms at the moment of BMs diagnosis more often showed declines in processing speed. BMs growth and age were not related to cognitive change. The change in cognitive performance was not related to either subjective cognitive performance or self-reported QoL. CONCLUSION Using a stringent RCI, we found patients who benefited from RT, but also patients who showed a clinical relevant cognitive decline three months post-RT. In most patients, this trend continued until at least eleven months after RT. Patients with multiple brain metastases may be particularly vulnerable to cognitive decline and death caused by tumour growth. However, life-extending RT also has its costs and thus requires careful consideration in shared decision-making regarding treatment options. GRANT INFORMATION The APRICOT study described in the current abstract as well as EG, were supported by funding from the Dutch Cancer Society “Koningin Wilhelmina Fonds (KWF)” (#11110).