Chronic inflammation and cancer: ASCO 2025 update

Summary Chronic inflammation has been recognized as a key contributor to cancer initiation, progression, and treatment response across various malignancies. In this short review we summarize the key takeaways from ASCO 2025 with regard to studies presented on chronic inflammation and cancer. Emerging evidence suggests that systemic inflammation can be modulated by lifestyle-based interventions such as diet or physical activity. Systemic inflammation may also contribute to complex symptoms such as cancer-related fatigue or depression, impairing quality of life. Markers of systemic inflammation such as the neutrophil-to-lymphocyte ratio can be used as prognostic markers and highlight the role of myeloid-driven inflammation in cancer. In line with this, clonal hematopoiesis—an aging-associated condition of clonal myeloid immune cell expansion—is commonly identified infiltrating solid cancers, shaping the immune landscape of the tumor microenvironment and thereby modulating cancer behavior and therapy effectivity.