Subcutaneous myxopapillary ependymoma presenting as a childhood sacrococcygeal tumor: a case report.

Subcutaneous myxopapillary ependymoma in a sacrococcygeal location is an uncommon lesion. We report such a case in a 16-mo-old female child, who presented with a sacrococcygeal mass since birth. The cytological picture was that of a malignant small round cell tumor and the diagnosis was missed on cytology, which was retrospectively confirmed on comparison with histology. Although rare, this lesion can be a potential diagnostic pitfall and needs to be distinguished from other malignant tumors occurring at this age and at a similar location, like sacrococcygeal teratoma with immature elements, primitive neuroectodermal tumor (PNET), and PNET with ependymal differentiation. Copyright 2002 Wiley-Liss, Inc.