It depends on the variability in the biology of these tumours which can express different catecholamine biosynthetic enzymes, secrete different vasoactive peptide (i.e., neuropeptide Y, adrenomedullin, or atrial natriuretic peptide) [7], present different symptoms related to tumour mass or present symptoms related to other organs involvement in syndromic forms. The gene discussed is NPPA; the disease is neoplasm.