The major pathways in which obesity promotes tumorigenesis include hyperinsulinemia/insulin resistance and insulin-like growth factor-I (IGF-I) abnormalities; sex hormone biosynthesis and pathway; low-grade inflammation and oxidative stress; alterations in adipocytokines; factors deriving from ectopic fat deposition; microenvironment and cellular disorders; disruption of circadian rhythms and dietary nutrients; altered intestinal microbiome; and mechanic factors in obesity [11,12,13]. This evidence concerns the gene IGF1 and obesity due to melanocortin 4 receptor deficiency.