November 2004: intradural mass of the cauda equina in a woman in her early 60s

Cauda equina neuroendocrine tumor: a report of three cases and review of the literature with focus on differential diagnosis and postoperative management

INTRODUCTION

Cauda equina neuroendocrine tumors (CENETs), previously described as cauda equina paragangliomas (PGLs) are rare and well-vascularized benign entities which can be often misdiagnosed with other intradural tumors more common in this anatomical site, such as ependymomas and neurinomas. We describe three cases of CENETs observed at our institution with particular focus on differential diagnosis and postoperative management. Since the lack of guidelines, we performed a literature review to identify factors that can predict recurrence and influence postoperative decision making.

CASE REPORT AND LITERATURE REVIEW

We report on three patients, two of them presenting with a clinical history of lower back pain and sciatica. In all cases magnetic resonance imaging (MRI) of the lumbosacral spine with and without Gd-DTPA revealed an intradural lesion with strong contrast enhancement, first described as atypical ependymoma or schwannoma. A complete tumor resection was achieved in all cases, the histopathological diagnosis classified the tumors as CENETs. In our literature review, a total of 688 articles were screened and 162 patients were included. Patients demographic data, clinical symptoms, resection and recurrence were recorded.

DISCUSSION

Differential diagnosis between CENETs and other more common tumors affecting cauda equina region, such as ependymomas or schwannomas (neurinomas), is still very challenging. Due to the lack of specific clinical or radiological characteristics, a correct preoperative diagnosis is almost impossible. With this paper we want to point out that CENETs must be considered in the differential diagnosis, most of all in case of entities with atypical radiological features. According to the literature, tumor recurrence after gross total resection is unlikely, while a long-term follow-up is recommended in case of subtotal resection or local aggressive behavior.

Gangliocytic paraganglioma of the spine

Paragangliomas are rare, encapsulated, benign neuroendocrine tumors that can arise from the adrenal medulla or extra-adrenal paraganglia. Extra-adrenal paragangliomas may develop a gangliocytic component with ganglion cells (Gangliocytic paragangliomas). Nearly 25%of cauda equina paragangliomas are gangliocytic paragangliomas. Here, we describe the case of a 35-year-old male who presented with weakness of both lower limbs over the last two months. Radiological findings were suggestive of myxopapillary ependymoma. However, the histopathological examination revealed a tumor with cells arranged in sheets, papillae, lobules, and around vessels forming pseudo rosettes. Ganglion cells were seen in small groups and, also singly. Tumor cells were immunopositive for chromogranin, synaptophysin, and S-100. Ganglion cells were immunopositive for synaptophysin, NSE, and NFP. A final histological diagnosis of Gangliocytic paraganglioma (WHO grade I) was made. To date, only nine gangliocytic paraganglioma cases have been previously reported, and to the best of our knowledge, this is the largest gangliocytic paraganglioma.

A Unique Case of an Aggressive Gangliocytic Paraganglioma of the Filum Terminale

Paragangliomas are rare neuroendocrine tumors that are mostly found in the head and neck. Even less common are gangliocytic variant paragangliomas of the spine for which there are only 7 other documented cases in the literature. We report a case of gangliocytic paraganglioma of the sacral spine in a 68-year-old man. The growth pattern is documented over three years, which to our knowledge has not previously been reported in the literature and is different from the natural history. Clinical, radiological, and pathological characteristics of the tumor are discussed in light of available reports of this rare tumor.