A cross sectional study in cognitive and neurobehavioral impairment in long-term nasopharyngeal cancer survivors treated with intensity-modulated radiotherapy.

Purpose/objectives: To determine neurocognitive and neurobehavioral impairment in long-term nasopharyngeal cancer survivors (NPC) treated with intensity-modulated radiotherapy (IMRT).

Materials/methods: A cross-sectional cohort of NPC ≥4 years (y) following IMRT was assessed. Objective cognitive function was measured using the Montreal Cognitive Assessment (MoCA) and patient-reported memory was assessed with the MDASI-HN problems remembering item. Patient and family ratings of patients' neurobehavioral symptoms of apathy, disinhibition and executive dysfunction were assessed with the Frontal Systems Behavior Scale (FrSBe). Other patient-reported symptoms (MDASI-HN), mood (HADS), and quality of life (FACT-H&N) were also collected.

Results: Among 102 participants: M:F = 66:36; median age 56y (32-77); median time since IMRT 7.5y (4.2-11.1). Impaired MoCA scores (<23) were observed in 33 (32%). Patient and family ratings of pre-illness neurobehavioral symptoms were in the normal range (total FrSBe T-scores 53.3 and 59.0 respectively). In contrast, post-treatment patient and family T-scores were clinically impaired (64.7, 71.3 respectively), with apathy, disinhibition and executive dysfunction post-treatment ratings all significantly worse than pre-treatment (p < 0.001). Prevalence of clinically significant post-treatment disturbance was high by patient and family ratings (48%/66% apathy, 35%/53% disinhibition, 39%/56% executive dysfunction). Post-treatment neurobehavioral symptoms strongly correlated with lower quality of life (r = -0.62) and higher anxiety (r = 0.62) and depression scores (r = 0.67, all p < 0.001). Total MoCA scores did not correlate with RT dose. However, greater declines in apathy, disinhibition and executive dysfunction were associated with receiving >75 Gy to temporal lobes.

Conclusion: NPC treated with IMRT had moderate to high rates of neurocognitive impairment and clinically significant apathy, disinhibition, and executive dysfunction.