Conclusion
Herein, we reported the case of an isolated cerebellar pontine angular embryonal tumor complicated by Cowden syndrome. Although its location did not meet the definition of medulloblastoma, the clinical, histological, and molecular genetic findings strongly suggested its presence. Therefore, the tumor was considered to be an “ectopic” medulloblastoma. Molecular genetic analysis is essential for revealing the underlying molecular genetic background of CNS embryonal tumors, NOS, as it can facilitate optimal treatment.