PTEN and Cowden disease: However, an extremely rare occurrence of a dysplastic cerebellar gangliocytoma (Lhermitte-Duclos disease) has been reported characterized by a germline loss of PTEN allele like Cowden disease.10 This highlights that although uncommon, gangliocytomas in different anatomical locations can occasionally display dysplastic changes and harbor identifiable genetic alterations, signifying the theoretical possibility of similar changes occurring in the neuronal component of sellar mixed tumors, although none were observed in our case.