Paraganglioma in the spinal cord histologically mimicking ependymoma – a case report

Abstract

Paraganglioma is a tumour lesion of neuroectodermal origin that occurs at various places in the human body, but is rarely observed in the spinal cord. Usually, it presents in the lumbar region (cauda equine and filum terminal) as a slow-growing painless tumour mass that causes local compression. We present a 53-year-old man with chronic low back pain, difficulty in walking, and impotence. The magnetic resonance study showed a tumour lesion suspicious for ependymoma. Surgical excision was performed and the result from the intraoperative frozen section was also ependymoma due to the presence of pseudorosettes structures. After the surgery, a thorough histological examination of the specimen revealed an encapsulated formation composed of ovoid and spindle-shaped cells with eosinophilic to light cytoplasm, with rounded nuclei with finely dispersed chromatin. An arrangement of cells in the form of pseudorosettes – ependymoma-like features was found in a large area of the tumour. Immunohistochemically, it was proved that the tumour was paraganglioma, not ependymoma. Paraganglioma is a rare tumour in the spinal cord and it should be distinguished from other tumours normally observed in this area like ependymomas by using immunohistochemical stains.