Prognostic Relevance of Inflammatory Cytokines Il-6 and TNF-Alpha in Patients with Breast Cancer: A Systematic Review and Meta-Analysis

Although cytokines mediate inflammation and inflammation facilitates cancer progression, few studies have evaluated the association between specific cytokines and the prognostic value of breast cancer. Therefore, this study aims to address the following question: What is the prognostic relevance of serum IL-6 and TNF-alpha levels on overall survival and treatment response in women with breast cancer? A systematic review and meta-analysis of cohort studies was conducted. The databases consulted included PubMed/Medline, Web of Science, and EMBASE. A total of 1748 articles were identified, of which 10 were included in the review. A significant association was found between elevated levels of IL-6 and TNF-alpha with poor overall survival and poor treatment response. The meta-analysis showed an HR of 3.74 (95% CI: 1.84–7.6) for elevated IL-6 with high heterogeneity (I²: 61%; p = 0.07) and an HR of 3.13 (95% CI: 1.57–6.23) for TNF-alpha with low heterogeneity (I²: 0%; p = 0.9). The overall response rate was 75% (95% CI: 31–100%; I²: 92%). In conclusion, IL-6 and TNF-alpha emerge as prognostic inflammatory biomarkers in women with breast cancer and are associated with poor survival and poor treatment response. This study highlights the need to establish an international consensus on cutoff points and standardized determination methods to implement these biomarkers in clinical practice.