Posterior fossa astroblastoma: a case report of an extremely rare tumor with challenging diagnosis in a child and a review of literature.

A 7-year-old boy presented to the hospital with recurrent nausea and vomiting over 2 weeks. A cranial MRI revealed a large heterogeneous lesion in the posterior fossa extending from the fourth ventricle to the foramen magnum with contact to the brainstem. The lesion showed moderate diffusion restriction and multiple small cystic components. The child underwent gross total resection. The primary histological findings suggested proliferative active tumor without further definition. The extended histological examination 3 weeks later confirmed the diagnosis of astroblastoma. Due to complete resection and full recovery of the patient, watchful waiting with radiological follow-up was recommended. Astroblastoma is an extremely rare tumor especially in the posterior fossa. However, it should be considered as a differential diagnosis in every tumor presenting the discussed radiological and histological features, especially in young aged patients.