Survivors of Head and Neck Cancer Can Experience Long-Lasting Cognitive Impairment

Comment: Two studies highlight that cognitive impairment is common and can impact quality of life in survivors of head and neck cancers. This should impact our counseling of patients and caregivers in terms of what to expect and what is “normal.” This is also a potential productive avenue of future research in terms of elucidating methods to reduce the neurocognitive morbidity of cancer treatment. —Jennifer Villwock, MD

How is neurocognitive function impacted after definitive radiation therapy for head and neck cancer (HNC)?

Bottom line
Head and neck cancer survivors have neurocognitive sequelae up to two years after definitive chemoradiotherapy or radiation treatment.

Background: Neurocognitive deficits (NCD) have been observed in noncentral nervous system cancers, yet short- and long-term neurocognitive data on patients treated for HNC are lacking.

Study design: Prospective, longitudinal study

Study setting: Princess Margaret Cancer Centre, Toronto, Canada.

Synopsis: Neurocognitive function and self-reported symptoms were assessed in 80 patients with histologically proven HNC requiring definitive chemoradiotherapy or radiotherapy and in 40 healthy controls four times (at baseline, and at six, 12, and 24 months after baseline) prior to commencing treatment. Neurocognitive test scores were converted to age-corrected z scores (mean, 0; standard deviation, 1) and reported as mean scores, standardized regression-based scores, and frequencies of impairments in intellectual capacity, concentration, memory, executive function, processing speed, and motor dexterity. Multivariable analysis was used to identify factors associated with NCD two years after treatment.

Eighty patients and 40 healthy controls were enrolled in the study. Analyses revealed significant differences between patient and control mean performance in some domains, with patient deficits increasing over time: intellectual capacity (Cohen d, effect sizes of -0.46, -0.51, and -0.70 for time points 6, 12, and 24 months, respectively); concentration/short-term attention span (-0.19, -0.38, -0.54); verbal memory (-0.16, -0.38, -0.53); executive function (-0.14, -0.34, -0.43), and global cognitive function composite (-0.38, -0.75, -1.06). There was an increased rate of impaired global neurocognitive functioning among patients (38%) at 24 months compared with the control group (0%). Neurocognitive deficits were not associated with baseline cytokines.

Citation: Zer A, Pond GR, Razak ARA. Association of neurocognitive deficits with radiotherapy or chemoradiotherapy for patients with head and neck cancer. JAMA Otolaryngol Head Neck Surg. 2018;144:71–79.

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What is the association between cognitive functioning and QoL in patients prior to treatment for HNC?

Bottom line
Cognitive impairment is common in patients with HNC and is associated with QoL and psychosocial variables. Together with previous research indicating that cognitive function and QoL can influence treatment adherence and outcomes, the results argue for the incorporation of cognitive screening and QoL assessment as part of pretreatment assessment for patients.