Track

Case Reports

Abstract

Myxopapillary ependymal rest is a benign form of ependymal heterotopia characterized by ectopic ependymal-type neuroglial tissue with myxopapillary architecture, typically located within the subcutaneous tissues of the sacrococcygeal region. It most commonly presents as a midline lumbosacral papule or nodule, although rare cases have been reported in the anterior perineal soft tissues. The clinical significance lies in its potential association with underlying spinal dysraphism, warranting further imaging and evaluation in select cases. The main diagnostic challenge is distinguishing myxopapillary ependymal rest from myxopapillary ependymoma, a low-grade neoplasm with potential for recurrence and metastasis. Ependymal rests characteristically lack mitotic activity, necrosis, and infiltrative borders, features that contrast with the more aggressive behavior of myxopapillary ependymoma. We present a case series of three pediatric patients with histologically proven sacrococcygeal myxopapillary ependymal rests. All patients presented with cutaneous lesions, one of which was clinically interpreted as a fibroepithelial polyp. Histopathologic examination confirmed the diagnosis in all cases. Myxopapillary ependymal rest should be included in the differential diagnosis of sacrococcygeal cutaneous lesions, particularly those resembling skin tags or acrochordons, and must be histologically distinguished from subcutaneous myxopapillary ependymoma and other fibroepitheliomas. Recognition of this entity is essential to avoid overtreatment and to assess for possible associated spinal dysraphism. Our findings underscore the need for clear terminology and diagnostic criteria in evaluating ependymal lesions of the sacrococcygeal region.