The most common known hereditary tumor syndromes that increase risk for PCC/PGL are Hereditary Paraganglioma Syndrome (SDHx), Neurofibromatosis Type 1 (NF1), von Hippel Lindau disease (VHL), Multiple Endocrine Neoplasia type 2 (MEN2, RET), TMEM127- and MAX-related hereditary pheochromocytoma, and Hereditary Leiomyomatosis and Renal Cell Cancer (HLRCC, FH) [6–8]. The gene discussed is RET; the disease is hereditary leiomyomatosis and renal cell cancer.