INS and skin basal cell carcinoma: The association between weight gain and BCC, if confirmed by other studies, may be mediated via alterations in the metabolism of endogenous hormones (sex steroids, insulin and insulin-like growth factors) (that lead to a change in the normal balance between cell proliferation, differentiation and apoptosis [11,12,33]), or through reduction in immunity [14], although this hypothesis is based on results of animal studies.