Association of Baseline Symptom Burden and Survival among Patients with Brain Metastases at a Tertiary Cancer Center

Abstract

<h3>Purpose/Objective(s)</h3> Brain metastases (BrM) commonly affect patients with solid malignancies and often correlate with significant symptomatology that profoundly impacts patients' quality of life (QOL). As systemic therapies increasingly improve extracranial disease control but lag in intracranial efficacy, a rising incidence of BrM persists. Thus, an urgent need exists to characterize the most common symptoms associated with BrM and to correlate these symptoms with survival. <h3>Materials/Methods</h3> We identified patients who received radiation therapy (RT) within 30 days of BrM diagnosis at a tertiary cancer center between 2017-2020 who prospectively completed the MD Anderson Symptom Instrument-Brain Tumor questionnaire (a validated instrument among patients with BrM for evaluation of 22 symptoms and 6 interference measures linked to daily functioning). Symptom severity score (range 0-10, with higher scores indicating more severe symptomatology) and interference score (range 0-10, with higher scores indicating greater compromise of activity-related/affective function), were compared via t-test or ANOVA by: age (>65 vs. ≤65), sex, Karnofsky performance status (KPS) (high, 90-100 vs. low, <90), Charlson co-morbidity index (CCI) (high, >2 vs. low, 0-2), primary tumor type (lung, breast, melanoma, other), and initial intracranial treatment strategy (surgical resection, stereotactic RT, or whole brain RT). Overall survival (OS) was assessed via Cox regression with the above co-variates; symptom severity and interference were evaluated in separate Cox models. <h3>Results</h3> A total of 101 patients were identified (median age=67 years, female=60%, primary lung cancer=45%). Mean symptom severity and interference scores at time of BrM diagnosis were 2.4 and 3.4, respectively. The most common severe (defined as a score >4) symptoms were: fatigue (47%), distress (40%), sleep disturbances (37%), drowsiness (35%), and sadness (32%). The most common high (score>4) interference measures were: enjoyment of life (47%), ability to work (44%), and walking (35%). Higher symptom severity was more common among females than males (2.8 vs 1.8, respectively; p=0.01); there were no significant differences in mean symptom severity or interference scores by age, KPS, CCI, or initial BrM treatment strategy. On Cox regression, higher symptom severity and higher interference scores were associated with worse OS (HR 1.30 per 1-point increase [95% CI, 1.11-1.51], p<0.001; and HR 1.18 per 1-point increase [95% CI 1.07-1.30], p=0.001, respectively); age, KPS, CCI, and other co-variates were not significantly associated with OS. <h3>Conclusion</h3> High symptom and interference burden is common among patients with BrM and associated with worse survival. Further work should investigate how improving symptoms, such as through palliative care interventions, may impact QOL trajectories and survival among the BrM patient population.