To assess the effects of expression levels of obesity-related genes on cancer survival rate, the expression levels of the 13 obesity-related genes (LEPR, POMC, MC4R, TMEM18, KCTD15, GNPDA2, SH2B1, MTCH2, NEGR1, FTO, LEP, PCSK1, and GPR120) were compared between normal tissues and cancer tissues. This evidence concerns the gene MC4R and obesity due to melanocortin 4 receptor deficiency.