Clinical Summary

• Real-world variability in cognitive symptoms was associated with poorer quality of life and greater social dysfunction in women with metastatic breast cancer.
• Researchers used daily ecological momentary assessments over 4 weeks to evaluate cognitive functioning in real-world settings.
• Findings support routine cognitive screening that assesses symptom variability, not only average symptom burden.

Cognitive dysfunction is common among metastatic breast cancer survivors (mBCS), yet little is known about how day-to-day cognitive fluctuations affect quality of life and social functioning. A prospective study presented at the 2026 Oncology Nursing Society (ONS) Congress evaluated whether “real-world cognitive functioning” predicts patient-reported outcomes in women living with metastatic breast cancer.

The study enrolled 51 women with metastatic breast cancer who completed baseline assessments, including the PROMIS Cognitive Function measure, followed by daily ecological momentary assessment (EMA) sessions over 4 weeks using the NeuroUX platform. Each daily assessment included a self-reported measure of cancer-related cognitive impairment (CRCI) symptoms and an executive functioning task called Color Trick.

Follow-up assessments at 4 weeks included the Functional Assessment of Cancer Therapy–General (FACT-G) quality-of-life measure and the Social Difficulties Inventory (SDI-16). Researchers calculated both person-specific average cognitive performance and within-person variability over time.

CRCI symptoms were reported in 73% of EMA sessions across participants. Regression analyses showed that baseline perceived cognitive functioning, variability in CRCI symptoms, and average Color Trick performance explained 39.7% of the variance in follow-up quality of life. Better quality of life was associated with better baseline perceived cognitive functioning, lower variability in CRCI symptoms, and lower average Color Trick scores over the 28-day assessment period.

For social dysfunction outcomes, baseline perceived cognitive functioning and variability in CRCI symptoms explained 40.3% of the variance. Greater social dysfunction was associated with worse baseline cognitive functioning and higher variability in cognitive symptoms.

The findings suggest that fluctuations in cognitive symptoms—not simply symptom severity—may meaningfully affect daily functioning and well-being in mBCS. Investigators noted that real-world cognitive functioning is dynamic and may be better captured through repeated assessments rather than single timepoint evaluations.

Clinically, the study highlights the importance of routine cognitive screening in metastatic breast cancer care. Oncology nurses may need to assess both average symptom burden and variability in cognitive symptoms over time to better identify patients at risk for reduced quality of life and impaired social functioning.

Investigators acknowledged several limitations, including the small sample size, lack of a control group, and relatively short monitoring period. They recommended larger studies with longer follow-up to confirm the observed associations.

This study provides preliminary evidence that day-to-day cognitive variability may serve as an important predictor of quality of life and social outcomes in women living with metastatic breast cancer.

Source:

Henneghan A, Van Dyk K, Hamajima Y, Moore R. Real World Cognitive Predictors of Quality of Life and Social Dysfunction in Women Living with Metastatic Breast Cancer. Presented at the Oncology Nursing Society Annual Congress; May 13-17, 2026. San Antonio, TX.