Systemic inflammation and risk of all-cause mortality after invasive breast cancer diagnosis among Hispanic and non-Hispanic white women from New Mexico

Introduction: Soluble tumor necrosis factor receptor-II (sTNF-R2), a pro-inflammatory biomarker, is associated with obesity and breast cancer (BC). The association between sTNF-R2 and risk of mortality after BC has not been studied, specifically among Hispanic women, an at-risk population due to their high prevalence of obesity and poor prognosis. We examined the association between sTNF-R2 and mortality among Hispanic and non-Hispanic white (NHW) BC survivors. Methods: A total of 397 invasive BC survivors (96 Hispanic, 301 NHW) contributed baseline interview data and blood samples. Hazard ratios (HR) and 95% confidence intervals (CI) were calculated using Cox proportional hazards regression models adjusting for clinical factors including body mass index. Results: After a median follow-up time of 13 years, 133 deaths occurred. The association between high vs low levels of plasma sTNF-R2 and mortality was not statistically significant overall (HR, 1.32; 95% CI 0.89-1.98). However, when stratified the mortality risk among Hispanic women was nearly 3-fold (HR, 2.83; 95% CI 1.21-6.63), while risk among NHW women was attenuated (HR, 0.99; 95% CI 0.61-1.61) (p-interaction=0.10). Conclusion: Our results suggest Hispanic BC survivors with high sTNF-R2 levels may have increased risk of mortality and could inform targeted interventions to reduce inflammation and improve outcomes.