PRKAR1A and blue nevus: CNC is characterized by two or more major manifestations of the syndrome, including lentigines, cutaneous and/or cardiac myxomas, breast myxomatosis, breast ductal adenoma, testicular Sertoli cell tumors, breast tumors, PPNAD, acromegaly, blue nevus, osteochondromyxoma, thyroid carcinoma and mutation of the PRKAR1a gene[7].