Multiple intradural-extramedullary ependymomas: proven dissemination by genetic analysis.

This 45-year-old woman was admitted with neck and back pain and difficulty in ambulation that had been progressively worsening for 2 years. Admission MR imaging revealed a cervicomedullary junction tumor and 2 intradural-extramedullary spinal tumors located separately at the levels of T5-6 and T8-9. All masses were successfully resected in a 2-stage operation. Histopathological examination of the surgical specimens revealed that all the lesions were ependymomas. Genetic analysis was performed to determine if the tumors were related. Conventional cytogenetics, multiplex fluorescence in situ hybridization (M-FISH), interphase-FISH specific to 22q11, and epidermal growth factor receptor loci analyses of the tumor samples revealed that the lesions originated from the same primary tumor. Although 3 simultaneous tumors in different compartments of the neural axis were diagnosed as ependymoma by histopathological examination, it was not possible to be sure if their multiplicity was due to spread of tumor cells via CSF or if it was due to multicentric foci. Thus, genetic analysis of the tumor samples is essential to confirm the exact mechanism of development of multiple ependymomas.