Patrick J Cimino1, Ashima Agarwal, Louis P Dehner. 1. Lauren V. Ackerman Laboratory of Surgical Pathology, St. Louis Children's Hospital, Washington University Medical Center, St. Louis, Missouri.
Abstract
BACKGROUND: Myxopapillary ependymomas (MEPN) are uncommon tumors of the central nervous system, mainly occurring within the conus medullaris-filum terminale. MEPNs can also present in the skin and underlying soft tissues of the sacrococcygeal region. The incidence of extramedullary MEPNs in children is unclear. PROCEDURE: We retrospectively reviewed our institutional files for MEPN cases between the years 1990-2012. A total of 11 pediatric and 38 adult cases were identified and compared to determine differences between these two distinct age groups. RESULTS: There were 40 (82%) tumors arising in the spine and nine (18%) in extramedullary sites. Pathologic examination revealed that extramedullary and spinal MEPNs were indistinguishable morphologically and immunophenotypically. Among the 11 children with MEPNs, seven had tumors presenting in extramedullary sites whereas only two adults (5%) had extramedullary tumors; this difference was highly significant (P < 0.0001). The lumbosacral portion of the spinal cord was the primary site for the remaining 40 MEPNs, four (10%) of which presented in children. One extramedullary MEPN (9%) recurred in a 45-year-old woman, and five (11%) of 40 spinal tumors recurred and/or metastasized; two of four children with spinal MEPNs developed recurrences and a manifestation to the aggressive nature of the latter tumor in the spinal cord of children. CONCLUSIONS: Based upon our experience, MEPN in children is more likely to present in the extramedullary soft tissues of the sacrococcygeal region where its behavior is more indolent than those tumors arising in the spinal cord in children.
BACKGROUND:Myxopapillary ependymomas (MEPN) are uncommon tumors of the central nervous system, mainly occurring within the conus medullaris-filum terminale. MEPNs can also present in the skin and underlying soft tissues of the sacrococcygeal region. The incidence of extramedullary MEPNs in children is unclear. PROCEDURE: We retrospectively reviewed our institutional files for MEPN cases between the years 1990-2012. A total of 11 pediatric and 38 adult cases were identified and compared to determine differences between these two distinct age groups. RESULTS: There were 40 (82%) tumors arising in the spine and nine (18%) in extramedullary sites. Pathologic examination revealed that extramedullary and spinal MEPNs were indistinguishable morphologically and immunophenotypically. Among the 11 children with MEPNs, seven had tumors presenting in extramedullary sites whereas only two adults (5%) had extramedullary tumors; this difference was highly significant (P < 0.0001). The lumbosacral portion of the spinal cord was the primary site for the remaining 40 MEPNs, four (10%) of which presented in children. One extramedullary MEPN (9%) recurred in a 45-year-old woman, and five (11%) of 40 spinal tumors recurred and/or metastasized; two of four children with spinal MEPNs developed recurrences and a manifestation to the aggressive nature of the latter tumor in the spinal cord of children. CONCLUSIONS: Based upon our experience, MEPN in children is more likely to present in the extramedullary soft tissues of the sacrococcygeal region where its behavior is more indolent than those tumors arising in the spinal cord in children.