Interleukin 2 (IL-2), IL-6, IL-8, tumor necrosis factor-alpha (TNF alpha), and C-reactive protein (CRP) are among the inflammatory markers believed to be associated with an increased risk of arrhythmia as well as commonly affected by various malignancies [12,13]. Another connection between cancer and AF involves the immune system. Here, TNF is linked to cardiac arrhythmia.