Cribriform-morular Thyroid Carcinoma Arising in a Medulloblastoma Survivor: Two Metachronous Tumors Shared with the Activation of the Wnt Signaling Pathway

Wnt signaling pathway activation is involved in the pathogenesis of a series of malignant tumors and is characterized by the nuclear accumulation of β-catenin protein. The occurrence of two or more Wnt pathway-associated tumors in a single individual is uncommon and generally attributed to inherited cancer syndrome, especially familial adenomatous polyposis (FAP). Herein, we presented a rare case of a child who suffered from the occurrence of Wnt-activated medulloblastoma and cribriform-morular thyroid carcinoma (CMTC) within a 9-year interval. She had no history of FAP and harbored an unexpected somatic mutation of the