About one in five patients who had completed primary breast cancer treatments but had not started endocrine therapy “had elevated memory and/or executive function complaints that were statistically significantly associated with domain-specific” neuropsychological test performances and depressive symptoms. Combined chemotherapy and radiation treatment in these patients “was also statistically significantly associated with memory complaints.” These and other findings from a prospective cohort study of 189 women diagnosed with stage 0 to IIIA breast cancer were published in the Journal of the National Cancer Institute.
The women were aged 21 to 65 years. “Most were white, married, college educated, and postmenopausal prior to their breast cancer diagnosis. Two-thirds received breast-conserving surgery; more than half had received chemotherapy; and three-quarters had received radiation therapy,” the researchers reported. Exclusion criteria included current or past disease of the central nervous system or a medical condition affecting cognitive function, as well as daily tobacco and alcohol use, and prior cancer diagnosis or chemotherapy treatment.
Neuropsychological testing “was conducted by a trained technician, closely supervised by a licensed clinical neuropsychologist,” the investigators explained. Self-report questionnaires were used to assess cognitive complaints in four subscales: memory, higher-level cognition measuring executive function, language and communication, and motor-sensory perception.
The researchers found that 23.3% of patients had higher memory complaints and 19% reported higher executive function complaints than found in age-matched healthy women without breast cancer. “Regression modeling demonstrated a statistically significant association of higher memory complaints with combined chemotherapy and radiation treatments (P = .01), poorer [neuropsychological] verbal memory performance (P = .02), and higher depressive symptoms (P < .001), controlling for age and IQ,” the researchers reported.
Higher memory complaints were not, however, statically significantly associated with chemotherapy alone. “For executive functioning complaints, multivariable modeling controlling for age, IQ, and other confounds demonstrated statistically significant associations with better [neuropsychological] visual memory performance (P = .03) and higher depressive symptoms (P < .001), whereas combined chemotherapy and radiation treatment (P = .05) approached statistical significance,” the investigators stated.
Value of Patient-reported Outcomes
“These results and other emerging studies suggest that subjective cognitive complaints in part reflect objective [neuropsychological] performance, although their etiology and biology appear to be multifactorial, motivating further transdisciplinary research,” the authors concluded. They also stated that their findings “add further support for the value of patient-reported outcomes as a central measurement in evaluation of cancer treatment-related morbidities.”
An accompanying editorial pointed out the true incidence of cognitive symptoms in patients with breast cancer may be underestimated and that neurocognitive, emotional, and behavioral symptoms can interfere with academic, vocational, and social pursuits. “However, many cancer survivors can enjoy improved levels of functioning if properly diagnosed and provided with the right support,” the editorial continues. “Symptom assessment coupled with effective and proactive intervention strategies are a critical component throughout and after cancer treatment.” ■