Paraganglioma of the Filum Terminale: Case Report, Pathology and Review of the Literature

Potential Anatomical Implications of Filum Terminale Paraganglioma on Coccygodynia: A Case Report

In this case report, we present a unique cause of coccygodynia due to an intradural lumbar spinal tumour in a patient with multiple filum terminale paragangliomas. We highlight the symptomatology, the clinical course, and the radiological findings. Our review of the literature proved our case to be the first report of an intradural cauda equina tumour presenting with coccygodynia in English literature. Based on the outcome and clinical response to treatment we make a bold hypothesis on the possible anatomical mechanism of his coccygodynia.

Immunohistochemical features of giant cell ependymoma of the filum terminale with unusual clinical and radiological presentation

BACKGROUND

Giant cell ependymoma of the filum terminale is a rare variant, generally manifested as a well-circunscribed intradural mass with an indolent biological behavior.

CASE PRESENTATION

We describe the case of a 48-year-old Mexican female who non-relevant past medical history, that developed a GCE of the filum terminale. Magnetic resonance imaging and computed tomography revealed the presence of an intra-axial tumor extending from L3 to L5 with extra-medullary invasion. Therefore the tumor was considered unresectable and only incisional biopsy was obtained, establishing the tentative diagnosis of a poorly differentiated neoplasia. A second evaluation of the case revealed the presence of numerous non-cohesive pleomorphic giant cells with intranuclear inclusions and broad eosinophilic cytoplasm, alternating with intermediate size cells with round, hyperchromatic nuclei and forming a perivascular pseudo-rosettes pattern. The ependymal phenotype was supported by light microscopy and corroborated by immunohistochemistry analysis. The patient was subsequently treated with radiotherapy 54Gy. She is alive after a 27-month follow-up, with residual disease, difficulty ambulating and pain.

CONCLUSIONS

GCE of filum terminale may have an atypical clinical and radiological presentation, albeit with invasive characteristics and anaplasia on histologic analysis. However, its biological behavior is indolent and associated to longer survival. Due to the presence of giant cells, the differential diagnosis of other primary neoplasias at that site were considered, including paraganglioma, malignant peripheral nerve sheath tumors as well as metastatic malignant melanoma, adrenal carcinoma, thyroid gland carcinoma and urothelial carcinoma, that may all harbor giant cells.