CDKN2A and benign neoplasm of parathyroid gland: Other specific genes whose pathways are linked to the development of parathyroid tumors, such as RIZ1, APC, RASSF1A, CDKN2A/p16, CDKN2B/p15, RB1, WT1, GATA4, PYCARD, SFRP1 and SFRP2, also appeared to be hypermethylated in both malignant and benign parathyroid tumors [40].