Paraganglioma of the Lumbar Spine: A case report and literature review

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.

A case of rare lumbar intradural tumor: paraganglioma

Lumbar paragangliomas are rare neuroendocrine neoplasms arising from specialized neural crest cells in the cauda equina/filum terminale region. They are difficult to diagnose radiologically and can be difficult to treat surgically if they secrete catecholamines. A 38-year-old woman presented with three and a half years of increasing lower back and sacrum discomfort. Her neurological examination was normal. The MRI revealed an L4 intradural lesion that was compressing the cauda equina. A total tumor resection was conducted. The paraganglioma was diagnosed by the pathology report. Paragangliomas should be considered in the differential diagnosis of intradural masses of the lumbar spine.

Cauda equina neuroendocrine tumors: A single institutional imaging review of cases over two decades

Cauda Equina Neuroendocrine Tumors (CE-NET), previously referred to as paragangliomas are a rare subset of spinal tumors, with limited data on imaging. Herein, we present a retrospective review of clinical and imaging findings of CE-NETs in ten patients who were evaluated at our institution over the past two decades. All patients had well-defined intradural lesions in the lumbar spine which demonstrated slow growth. A review of imaging findings revealed the presence of an eccentric vascular pedicle along the dorsal aspect of the tumor in 8 of the 10 patients (eccentric vessel sign), a distinctive finding that has not previously been reported with this tumor and may help improve the accuracy of imaging-based diagnosis. In all cases, a gross-total resection was performed, with resolution of symptoms in most of the cases.

SDH-B, INSM1, and GATA3 expression in cauda equina neuroendocrine tumors: Report on 21 cases from a north Indian tertiary care centre

BACKGROUND

Primary neuroendocrine tumors (NETs) of the central nervous system (CNS) are rare, primarily seen in the cauda equina region, known as cauda equina NETs. This study was carried out to evaluate the morphological and immunohistochemical characteristics of cauda equina NETs.

MATERIAL AND METHODS

All cases of histologically proven NETs that originated within the spinal cord from 2010 to 2021 were retrieved from the surgical pathology electronic database. For each case, the clinical presentation, site, radiological features, functional status, and pre-operative diagnosis were recorded. Immunohistochemical stains for GFAP, synaptophysin, chromogranin A, cytokeratin 8/18, INSM-1, Ki67, GATA3, and SDH-B were performed for every case using automated immunostainer. GATA3 immunohistochemistry was repeated manually.

RESULTS

A retrospective probe of records revealed 21 cases of NETs having a mean age of 44 years and slight male dominance (M:F ratio 1.2:1). Cauda equina was the most prevalent site of involvement (19, 90.5%). The most typical presentation was lower backache and weakness of bilateral lower limbs. The histopathological features were similar to NETs seen at other sites. Reactivity for at least one neuroendocrine marker was seen in all cases while GFAP was negative. Cytokeratin 8/18 was expressed in the majority (88.9%) of cases. INSM1 and GATA3 expression was seen in 20 (95.2%) and 3 (14.3%) cases, respectively. All cases retained SDH-B cytoplasmic staining. Higher Ki67 index (>3%) was associated with higher risk of recurrence.

CONCLUSIONS

Cauda equina NETs rarely express GATA3 and are unlikely to be associated with SDH mutations. Recurrent cases may be negative for synaptophysin, chromogranin, and cytokeratin; thus INSM1 IHC is helpful.

Paraganglioma in a Young Adult Female Patient: A Case Report

Paragangliomas are catecholamine-secreting neuroendocrine tumors that originate from the chromaffin cells of the sympathetic ganglia. Roughly 10% of paragangliomas are malignant, resulting in a rare occurrence of 90-95 cases per 400 million people. Herein, we report a case of a 29-year-old female patient who presented with nausea, vomiting, and bloating and was found to have a large left retroperitoneal tumor upon imaging. The tumor was successfully removed, and subsequent histological analysis was compatible with the presence of a paraganglioma. This case serves as a reminder that despite its rarity, paragangliomas should never be dismissed as a differential diagnosis if correlating symptoms and diagnostic findings are consistent with that of paraganglioma etiology.

Primary Paraganglioma of the Spine: A Systematic Review of Clinical Features and Surgical Management in Cauda Equina vs Non-Cauda Equina Lesions

BACKGROUND

Primary spine paragangliomas are rare tumors. Surgical resection plays a role, but aggressive lesions are challenging. We reviewed the literature on primary spine paragangliomas.

METHODS

PubMed, Scopus, Web of Science, and Cochrane were searched upon the PRISMA guidelines to include studies on primary spine paragangliomas. Clinical-radiological features, treatments, and outcomes were analyzed and compared between cauda-equina vs non-cauda-equina tumors.

RESULTS

We included 143 studies comprising 334 patients. Median age was 46 years (range, 6-85). The most frequent symptoms were lower-back (64.1%) and radicular (53.9%) pain, and sympathetic in 18 patients (5.4%). Cauda-equina paragangliomas (84.1%) had frequently lumbar (49.1%) or lumbosacral (29%) locations. Non-cauda-equina tumors were mostly in the thoracic (11.4%), thoracolumbar (5.1%), and cervical (3.6%) spine. Median tumor diameter was 2.5cm (range, 0.5-13.0). Surgical resection (98.5%) was preferred over biopsy (1.5%). Decompressive laminectomy (53%) and spine fusion (6.9%) were also performed. Adjuvant radiotherapy was delivered in 39 patients (11.7%) with aggressive tumors. Post-treatment symptomatic improvement was described in 86.2% cases. Median follow-up was 19.5 months (range, 0.1-468.0), and 23 patients (3.9%) had tumor recurrences. No significant differences were found between cauda-equina vs non-cauda-equina tumors.

CONCLUSION

Surgical resection is effective and safe in treating primary spine paragangliomas; however, adjuvant treatments may be needed for aggressive lesions.

Paraganglioma of the cauda equina: a tertiary centre experience and scoping review of the current literature

Cauda equina paragangliomas are rare benign extra-adrenal neuroendocrine tumours arising from the neural crest cells associated with autonomic ganglia. These tumours are often mistaken preoperatively for ependymomas or schwannomas. Patients present with axial or radicular pain with or without neurological deficits. Recurrence, secretory features and length of follow-up are controversial. We conducted a retrospective cohort study of paraganglioma through searching a prospectively maintained histopathology database. Patient demographics, presentation, surgery, complications, recurrence, follow-up and outcome between 2004 and 2016 were studied. The primary aim was to collate and describe the current evidence base for recurrence and secretory features of the tumour. The secondary objective was to report outcome and follow-up strategy. A scoping review was performed in accordance with the PRISMA-ScR Checklist. Ten patients were diagnosed (M:F 7:3) with a mean age of 53.6 ± 5.1 (range 34–71 years). MRI scans revealed intradural lumbar enhancing lesions. All patients had complete microsurgical excisions without adjuvant therapy with no recurrence with a mean follow-up of 5.1 ± 1.4 years. Tumours were attached to the filum terminale. Electron microscopic images demonstrated abundant neurosecretory granules with no evidence of catecholamine production. A total of 620 articles were screened and 65 papers (including ours) combining 121 patients (mean age 48.8 and M:F 71:50) were included. The mean follow-up was 3.48 ± 0.46 (range 0.15–23 years). Back pain was the most common symptom (94%). Cure following surgery was achieved in 93% of the patients whilst 7% had recurrence. Total resection likely results in cure without the need for adjuvant therapy or prolonged follow-up. However, in certain situations, the length of follow-up should be determined by the treating surgeon.

Paraganglioma of the filum terminal: Case report and review of the literature

Paraganglioma of the filum terminal/cauda equina is a rare slow growing tumor which originates from the ectopic sympathetic neurons. Surgically, total excision may be difficult for this well demarcated tumor surrounded by couple of rootlets but is usually possible in nearly all cases. Actually, final diagnosis cannot be determined intraoperatively, but is possible only after an immunohistochemical staining. Herein, the authors present a middle age woman whose initial symptoms were lower back pain and radiculopathy. Her MRI was found to be compatible with a cauda equina tumor. During her excisional surgery a hard and relatively vascular tumor was fully removed. The Immunohistochemical results were compatible with paraganglioma of the filum terminale. In addition to case presentation, thorough review of the literature is also done.

Microsurgical Management of a Primary Neuroendocrine Tumor of the Filum Terminale: A Surgical Technique

Neuroendocrine tumors (NETs) are benign tumors of the autonomic nervous system that rarely occur in the spinal canal. The gold standard treatment is gross total resection while preserving the patient’s neurologic functioning as complete surgical resection is curative. The surgical management of NETs could pose a challenge given their friable consistency, hypervascular nature, and proclivity to adhere to the cauda equina nerve roots.

We present a case of a 62-year-old female with an incidental primary NET arising from the filum terminale internum, review the literature, and describe the surgical technique including the benefits of using an intraoperative ultrasound and some of the pitfalls of relying “blindly” on neuromonitoring. Early identification and disconnection of the tumor’s vascular pedicle, which usually runs through the cranial filum, devascularizes the tumor, prevents systemic complications from catecholamine release, and facilitates circumferential dissection off the en passage cauda equina nerve roots. Our patient remains neurologically intact and asymptomatic two years postoperatively and neuroimaging confirmed complete resection.

Primary Lumbar Paraganglioma: Clinical, Radiologic, Surgical, and Histopathologic Characteristics from a Case Series of 13 Patients

BACKGROUND

Paragangliomas are uncommon neuroendocrine tumors, rarely occurring in the lumbar spine. Primary lumbar paragangliomas are prominently vascularized, can present variably, and pose both diagnostic and surgical challenges. We report on a large case series with long-term follow-up and intraoperative footage to characterize the natural history, diagnostic approach, and operative approach to this rare surgical disease.

METHODS

This is a single-center, retrospective cohort study including all patients with histologically confirmed primary lumbar paraganglioma treated at our tertiary neurosurgical center between 1997 and 2018. Clinical, radiologic, surgical, and histologic data were collected from medical records.

RESULTS

There were 13 cases of primary lumbar paraganglioma (8 men [61.5%], 5 women [38.5%]; mean age, 51.3 years; range, 33.2-68.9 years). Symptom duration correlated with tumor size (Spearman r = 0.735, P = 0.01). The main presenting symptoms were lower back pain and radiculopathy, often long-standing with recent deterioration. Seven patients (53.8%) were admitted as emergency cases, including 3 with cauda equina syndrome. Preoperative differential diagnoses included nerve sheath tumor, ependymoma, meningioma, and disk herniation. The mean Ki-67 mitotic index was 5.7% (range, 1%-10%). Surgical resection improved pain in 8 of 13 patients (61.5%) and weakness improved in 5 of 5 patients (100%).

CONCLUSIONS

Primary lumbar paragangliomas are rare neoplasms of the cauda equina that typically progress slowly but may also present acutely. They are often related to the filum terminale, which should be resected prior to other attachments intraoperatively to prevent displacement of the tumor out of view. Total resection can be curative, and long-term follow-up in this series found no recurrence.

Paragangliomas of the spine: a retrospective case series in a national reference French center

INTRODUCTION

Primary paragangliomas (PG) of the spine are extremely rare entities. The present study reviews our experience over a period of 30 years.

METHODS

This is a retrospective, single center, observational study. Patients surgically treated for a spinal PG with confirmed anatomopathological diagnosis were included. The McCormick classification was used as a reference for clinical evaluation. Follow-up MRI and clinical assessment took place at 6 weeks, 3 months, 6 months, and 1 year after surgery and on yearly basis after.

RESULTS

Six cases have been operated in our institution. The mean age was 37.8 (median 35.5, 30-53). The mean follow-up period was 9.6 years (median 9.5, 1-23). Preoperative duration of symptoms varied between a few hours to 4 years. Low back pain was most common sign. One presented with hemorrhage and acute onset of paraplegia. All patients underwent single surgery, with the exception of one case, which had two surgeries on the same anatomical site and a third surgery on another location of the same tumor type. Preoperatively, McCormick scale was I in four cases, and II and IV in one case, respectively. Postoperatively, all patients in McCormick I retained the same class; one patient in McCormick II passed to McCormick III; the case in McCormick IV recovered to McCormick II. Five of eight surgeries achieved total resection, while two surgeries accomplished a partial microsurgical excision and one a gross total resection. Three patients had spinal leptomeningeal dissemination. Two of them benefited from extended spine radiotherapy, while the other of a "wait-and-scan" policy. Spinal leptomeningeal dissemination was stable in all patients at last follow-up.

CONCLUSION

We consider surgery as primary treatment in all PG. In our experience, preoperative diagnosis is difficult and caution must be taken to perioperative course in these cases. We do not routinely perform postoperative radiation if there is a residual tumor. We regularly perform clinical and radiological follow-up, so as to be able to document recurrent cases, which have been reported even up to 30 years after primary surgical excision.