Therefore, it is cancer itself and the treatment that greatly compromise the bioavailability of nutrients, as well as their absorption, leading to a degeneration in body composition (reduced lean mass, and increased fat mass and total body mass), in systemic inflammation (increased interleukin (IL)-6, IL-8, C-reactive protein (CRP), and tumor necrosis factor-α (TNF-α)) [3,4]. Here, TNF is linked to cancer.