The activity of hormone-dependent isoenzymes stearoyl coenzyme A desaturase (SCD) and fatty acid desaturases (FADS1 and FADS2) is significantly higher in the peritumoral zone than in the tumor center designating a more active biosynthesis of monounsaturated fatty acids and polyunsaturated fatty acids [65]. The gene discussed is SCD; the disease is neoplasm.