CXCL8 and depressive symptom measurement: Evidence supporting a role of cytokines, especially IL-1, IL-6, IL-8, and TNF-α, in the pathophysiology of depression and anxiety, combined with the presence of high levels of these molecules in cancer patients, including CRC [9, 10], suggests that cytokines play a role in the etiology and pathophysiology of depression and anxiety in these subjects.