Sacral ependymoma presents 20 years after initial posterior fossa lesion

Abstract

Posterior fossa ependymomas (PFEs) are designated histologically as low-grade neoplasms. Despite being characterised as benign, cases of metastasis have been reported only a few times with the patients concurrently diagnosed with the primary tumour. Interval drop metastasis or spontaneous second distal tumours are extremely rare and, in most cases, are diagnosed within a few months of primary tumour resection. Here, we report a patient with a grade 2 paediatric PFE exhibiting a 20-year interval to a second sacral ependymoma. The patient was initially diagnosed with a PFE at the age of 10 years and underwent tumour resection and postoperative radiotherapy. In their late 20s, the patient presented with basilar artery occlusion complicated by life-threatening epistaxis. Post-thrombolysis, the patient presented with a large sacral grade 1 myxopapillary ependymoma with cauda equina syndrome-like symptoms. Here, we present a rare case of two ependymomas with a 20-year interval in the same patient with compounding comorbidities.

Keywords: Cancer intervention; Neurooncology; Radiology; Stroke.

Figure 1

Patient imaging and pathology of the tumour. (A, B) Contrast CT scan of the abdomen and pelvis along with (C, D) sagittal T2 and T1 MRI showing the destruction of the sacrum by a large, predominately cystic slow mass, indicative of a myxopapillary ependymoma. There is bilateral extradural extension into the piriformis muscles and there is no involvement of the sciatic nerves. Red box/ellipses indicate the sacral mass. (E) Histopathology image suggestive of an infarcted tumour and viable regions positive of glial fibrillar acidic protein and epithelial membrane antigen. Secondary reactive changes are evident along with normal appearing skeletal muscle fibres. The appearances are thought to represent a glial tumour, most likely myxopapillary ependymoma WHO grade 1.