Diagnosis: subcutaneous myxopapillary ependymoma

Abstract

Discussion MRI demonstrated a 6.7 × 6 × 6 cm lobular fluid signal intensity mass arising from the midline natal cleft abutting the coccyx, with multiple hypointense internal septa (Fig. 1). The mass was well-circumscribed and confined to the intergluteal fold subcutaneous tissues. The distal thecal sac, cauda equina and conus were normal. An ultrasound-guided biopsy was performed to exclude a soft tissue sarcoma. Tumour resection histology showed a pseudopapillary architecture with a central core composed of PAS-positive myxohyaline matrix, and small vessels around which relatively uniform cuboidal to columnar cells were arranged. Mild cytological atypia was noted with low mitotic count. Characteristic immunoprofile included S100 and GFAP cytoplasmic positivity, while cytokeratin was negative (Fig. 2). A diagnosis of subcutaneous myxopapillary ependymoma (MPE) was made. Ependymomas are common spinal tumours, with an average age of 35 years and a male predilection [1, 2]. A minority The case presentation can be found at