Pediatric nondura-based clear cell meningioma of the cauda equina: case report and review of literature

Intraspinal clear cell meningioma without dural attachment: A case report and literature review

RATIONALE

Clear cell meningioma (CCM) is one of the rarest but most aggressive forms of meningioma, with a tendency to occur at a high recurrence rate. Intraspinal CCM, especially the nondura-based type, is even rarer than the intracranial CCM.

PATIENT CONCERNS

We report a case of a 45-year-old woman who presented with a 1-month history of episodic pain in the lower back and in both thighs in the front side. Femoral nerve stretch tests were positive on both sides. Magnetic resonance imaging (MRI) demonstrated an intradural tumor at the L3 level, which was isointense on T1- and T2-weighted images (WI) and homogeneously enhanced on gadolinium-contrast T1 WI.

DIAGNOSES

The space-occupying lesion was pathologically confirmed as CCM.

INTERVENTIONS

During surgery, we found that the tumor adhered to a nerve root, without dural attachment. The nerve root was partially removed to achieve complete resection.

OUTCOMES

The pain disappeared after the operation. The 1 year follow-up MRI revealed no evidence of tumor recurrence or metastasis.

LESSONS

Nondura-based intraspinal CCM is easier to completely remove, and such complete removal should be achieved during the first operation. Although the recurrence rate of this particular type of meningioma appears to be lower than that of other types, close clinical and radiological follow-up is necessary.

A Giant Nondural-Based Lumbosacral Clear Cell Meningioma Mimicking Schwannoma: A Case Report and Review of the Literature

Spinal clear cell meningiomas (CCMs) are rare and dural-based lesion usually affecting the younger population. We report the rare case of giant nondural-based spinal CCM mimicking schwannoma and review the literature. A literature search was performed at PubMed and Embase until January 1, 2020. A total of 19 cases of nondural-based spinal CCM was reported. The following relevant data were extracted: authors, publication year, patient and tumor characteristics, treatment, and outcome. The mean age of the presentation was 20.58 years. Twelve (63.16%) were female and seven patients (36.84%) were male. The most common location was lumbosacral region 15 (79%). Fifteen (79%) tumors had cranio-caudal dimension ≤2 vertebral level, and only four (21%) tumors had dimension ≥2 vertebral level. Gross total resection (GTR) was performed in 18 (95%) patients and subtotal resection (STR) in 1 patient. Recurrences were reported in five (26.14%) patients. Four of them showed recurrences within 6 months; earliest at 2.3 months in the patient had undergone STR. Our patient is 19-year-old male diagnosed with a lumbosacral intradural lesion. Craniocaudal dimension is ≥2 vertebral level shows the foraminal extension and vertebral scalloping. GTR is performed. Intraoperatively, the tumor has foraminal extension and shows attachment with right S1S2 nerve root. No dural attachment is found. Six-month follow-up magnetic resonance image shows no evidence of disease. Nondural-based spinal CCMs are extremely rare and should be kept as a differential diagnosis in young patients with giant intradural tumor, and whose radiological features suggesting of schwannoma. It affects young patients and usually involves more than one vertebral level. The chances of recurrences and metastasis are always high even after GTR; hence, close follow-up of the entire neuraxis is warranted.

Intraoperative Anatomical Findings in Pediatric Clear Cell Meningioma of the Lumbar Spine: Case Report and Literature Review

Clear cell meningioma (CCM) is a WHO classification Grade II meningioma. It is a very rare disease, of which only 41 cases of spinal cord CCM in children have been reported to date. CCMs sometimes do not have the “dural attachment” that is usually found in meningiomas, and our understanding of the origin of CCMs is therefore controversial. We hereby present a case of pediatric CCM of the lumbar spine, in which we examined intraoperatively, the detailed anatomical location of the tumor. The case is a 10-year-old boy, who presented to our hospital with a 2-month history of lower back and bilateral lower extremity pain upon waking, which gradually worsened. Lumbar spine CT and MRI revealed an intradural extramedullary tumor at the L3 vertebral level, and surgery was performed to remove it. The tumor was in close contact with the dura mater, and also in contact with the cauda equina via the arachnoid. The tumor was likely located primarily between the dura mater and arachnoid. The pathological diagnosis was CCM, with an MIB-1 index of less than 1%. His back pain and bilateral lower extremity pain improved after surgery, and he was discharged from our hospital. Postoperative radiation therapy was not performed. Based on this case, we suggest that intraoperative examination of the anatomical location of these tumors and accumulation of relevant experience are important to elucidate the embryological mechanisms of this rare disease.

Rare intraspinal clear cell meningioma in children: a case report and literature review

Meningioma of the spinal canal is very rare. Clear cell meningioma (CCM) with special histological features occurs more commonly in the spinal cord. A review of the published English-language literature identified 40 reported cases of children with intraspinal CCM and this current report presents an additional case of a 3-year-old child with confirmed lumbar CCM. The current case underwent gross total resection of the CCM. At 9 months after the operation, lumbar magnetic resonance imaging was undertaken and confirmed the absence of tumour recurrence. The child was able to walk normally again. During this period, the child did not receive adjuvant treatments such as radiotherapy and chemotherapy. An evaluation of the 41 cases demonstrated the following: (i) there was no significant difference between the recurrence rate of females and males; (ii) there was a significant difference in the recurrence rate based on the extent of resection (gross total resection versus partial resection); (iii) the recurrence rate in patients where the number of involved segments ≥3 levels was significantly higher than that in patients where the number of involved segments was 1–2 levels. For children with CCM, complete surgical resection might be an important characteristic for predicting the risk of the recurrence of CCM.

Spinal Clear Cell Meningiomas: Clinical Features and Factors Predicting Recurrence

OBJECTIVE

As a World Health Organization grade II tumor of the nervous system, clear cell meningioma (CCM) is an uncommon histologic variant of meningioma. Spinal CCMs are even rarer, with <100 spinal CCMs reported in the English literature. We present this study to characterize clinical manifestations of spinal CCMs and determine the factors predicting recurrence.

METHODS

A literature search was performed for relevant case reports and series in PubMed and Embase until September 1, 2019. These articles were reviewed to identify clinical features, treatment modalities, and prognosis of patients with spinal CCMs.

RESULTS

Eighty-four spinal CCMs were analyzed. Of these patients, 36 (42.9%) were young (age ≤18 years), and the mean age at resection was 24 years. Fifty-three patients (63.1%) were female and 31 (36.9%) were male. Most of the tumors (56/84, 66.7%) were located in the lumbar region. In 31 patients (36.9%) >2 segments in the craniocaudal direction were involved (number of involved segments ≥3 levels). Gross tumor resection was performed in 77 patients (91.7%). Twenty patients (23.8%) showed radiographic evidence of recurrence during follow-up. Recurrence-free survival at 1, 5, and 10 years after resection of spinal CCM was 87%, 71%, and 47%, respectively. Multivariate analysis showed that age ≤18 years (hazard ratio [HR], 3.64; P = 0.024), subtotal resection (HR, 3.43; P = 0.031), and segments involving ≥3 levels (HR, 5.66; P = 0.002) were associated with increased recurrence.

CONCLUSIONS

Spinal CCMs have their own unique clinical features compared with conventional spinal meningiomas and intracranial CCMs. Spinal CCMs have a predilection to affect younger patients, are prone to appear in the lumbar region, and have a high recurrence rate. Age ≤18 years, subtotal resection, and involvement of long segments (≥3 levels) are positive predictors of recurrence.