Extraneural Metastasis in Intracranial Tumors in Children: the Experience of a Single Center

Our aim is to evaluate the clinical features and outcomes of children with primary central nervous system (CNS) tumors who develop extraneural metastasis (ENM). We retrospectively evaluated children diagnosed with primary CNS tumors treated at our institution between 1972 and 2004. Of 1,011 patients these tumors, 10 (0.98%) developed ENM. The histopathologic diagnosis was medulloblastoma in six patients, germ cell tumors in two patients, and ependymoma and atypical teratoid rhabdoid tumor (ATRT) in one patient each. In six patients, the primary tumor was located in the posterior fossa; it had a supratentorial location in the patient with ATRT, was located in the sellar and suprasellar region in the two patients with germ cell tumors, and was found in the distal spinal cord in the patient with an ependymoma. In two patients ENM was detected at the time of diagnosis. In other patients ENM developed between 9 and 25 months after diagnosis. Metastatic sites included bone, bone marrow, lung, cervical lymph nodes, liver, and paranasal sinuses. Of the 10 patients who developed ENM, 8 died of their disease 0.27-16.2 months (median, 2.60 months) after it was detected. One patient with dysgerminoma is alive, without disease, 117.80 months after diagnosis of the ENM. One patient with germ cell tumor is alive with disease 11.3 months after diagnosis of the ENM. Systemic metastasis to other extraneural sites is extremely rare in children with intracranial tumors. In our series the rate of ENM is 0.98%. The liver and lung are the most common site for metastasis, followed by the bone and bone marrow. The outcome is poor in patients with CNS tumors with ENM.