Giant pediatric intraventricular meningioma: Case report and review of literature.

Intraventricular meningiomas are rare in the pediatric population. These tumors are often large in size and aggressive in behavior when they occur in children. The management of these tumors is a surgical challenge.

Introduction

Intracranial meningiomas are rare in children. They form about 0.5%–5% of central nervous system (CNS) tumors in the pediatric age group.[1] The management of these tumors is challenging as they are usually large at presentation. Here, we present a case of a 7-year-old female child with a large intraventricular meningioma who presented to us features of raised intracranial pressure. We also reviewed literature for pediatric intraventricular meningiomas.

Case Report

A 7-year-old female child born of a nonconsanguineous marriage presented to us with headache for the last 20 days, which was insidious in onset, dull aching type, and frontal in location to begin with but progressively worsened in severity over the next few days. It used to be worse in the early morning and was associated with vomiting. The vomiting used to relieve headache. She gave no history of loss of consciousness, seizures, diminution of vision, diplopia, facial asymmetry, difficulty in hearing, change in voice, nasal regurgitation of fluids, or difficulty in swallowing. The patient's antenatal and perinatal period was uneventful, and she had achieved normal developmental milestones. She also had an elder sibling who was developmentally normal to age according to parents. The child was conscious, alert, and playful. She had an enlarged head. Papilledema was present on fundus examination. She had no other neurological deficits and there were no neurocutaneous markers. A contrast-enhanced magnetic resonance imaging of the brain [Figure 1] revealed large lobulated lesion of size 6.4 cm × 6.3 cm × 8.3 cm which was hypointense on T1, hyperintense on T2, intensely enhancing within the body of the left lateral ventricle causing dilatation of lateral ventricle, causing significant mass effect. Based on radiology, a differential diagnosis of choroid plexus papilloma and intraventricular meningioma was considered. The patient was taken for surgery after informed consent and neuronavigation guided posterior temporal craniotomy flap was raised. Durotomy was done in C-shaped fashion and reflected anteroinferiorly. Navigation guided corticectomy was done in middle temporal gyrus to approach the tumour in left trigonal area. Tumor was completely intraventricular and extended from the left temporal horn to the atrium and body of the left lateral ventricle. It was highly vascular but variable in consistency, i.e. soft at certain areas and firm to hard in others. Gross total excision was done and a ventricular drain was placed. The duration of surgery was 9 h. Intraoperative blood loss was 3000 ml, but there were no episodes of bradycardia, hypotension, desaturation, or hypothermia. The patient was extubated and had no neurological deficits in the postoperative period. Postoperative noncontrast computed tomography of the head [Figure 2] done revealed no residual tumor. The ventricular drain was removed on the second postoperative day. Histopathology report [Figure 3] revealed a moderately cellular tumor composed of sheets and whorls of round to oval cells with moderate amount of eosinophilic cytoplasm with mild nuclear atypia suggestive of Grade 1 meningioma. The MIB index was 2%.

Figure 1

(a) T1 sagittal, (b) T2 axial, (c) T2 coronal, (d) contrast axial, (e) contrast coronal, (f) contrast sagittal

Figure 2

Postoperative noncontrast computed tomography of the head showed no residual tumor

Figure 3

Histopathology showed a moderately cellular tumor composed of sheets of cells with eosinophilic cytoplasm with mild nuclear atypia

Discussion

Meningiomas in children tend to occur in the latter part of the first decade or early second decade.[2] They form about 0.5%–5% of CNS tumors in them.[1] This is much less as compared to adults where they are about 30% of the total, of which only 3%–4% are intraventricular.[3] In children, however, a much larger proportion (10%–15%) are intraventricular and usually occur in the trigone of the lateral ventricles.[3] In another sharp contrast with the adults, meningiomas in the pediatric population are more common in males.[14] This is probably due to the absence of effect of sex hormone on steroid receptors. A significantly higher proportion (up to 40%) of these tumors is associated with neurofibromatosis.[23] The patients with neurofibromatosis are more likely to present with multiple tumors.[2] Prior radiation exposure, especially in cases of childhood, leukemia has been reported to predispose to development of meningiomas.[3]

As in our case, the usual presentation is with symptoms of raised intracranial pressure.[56] Neurological deficits or lateralizing signs are usually absent due to intraventricular location. Some patients may present with seizures which are mostly generalized type.[2] Overall, the incidence of seizures is reported to be lower than that of adults.[2]

Pediatric meningiomas are usually large at presentation. As previously mentioned, this is probably due to the fact that these tumors produce no or minimal symptoms in children. They also exhibit a higher frequency of cystic change as compared to their adult counterparts.[12] Due to derivation from leptomeningeal rests lodged in parenchyma, choroid plexus, tela choroidea, or velum interpositum, these tumors lack dural attachment and are more likely to be intraparenchymal or intraventricular in children.[56] A differential diagnosis of choroid plexus papilloma, ependymoma, primitive neuroectodermal tumor, teratoma, or cavernoma must be considered in these cases.

Operating on these large tumors, especially in children, is challenging more so with their peculiar location such as in intraventricular location, in the skull base, or in the Sylvian fissure.[2] Surgical trajectory to tumors within the atrium requires consideration of the location of the optic radiation which lies lateral and inferior to atrium. These tumors may even derive their blood supply from internal carotid artery or its branches which make embolization hazardous and of questionable benefit.[2] About 10% of patients succumb to perioperative complications due to excessive blood loss during surgery, meningitis, or neurological deficits due to venous infarcts.[2]

Pediatric meningiomas frequently demonstrate brain invasion. They are aggressive tumors with 40%–60% of these being Grade 2 or 3. 1p and 14q deletion have also been reported and are associated with increased recurrence.[6]

Radiation therapy is indicated for residual lesions, high-grade tumors, or recurrent tumors. Radical tumor excision with adjuvant radiotherapy improves the recurrence-free survival in children with malignant meningiomas.[2]

Overall prognosis is poor as compared to adults. Outcomes for intraventricular meningiomas have not been reported separately. Subtotal resection is associated with a worse outcome. Outcome is also poor in tumors with higher grade, lesions that demonstrate cortical invasion and in patients with neurofibromatosis.

Reported cases of pediatric intraventricular meningioma are tabulated in Table 1.

Table 1

Reported cases of pediatric intraventricular meningiomas

Conclusion

Pediatric intraventricular tumors are rare tumors. The management of these tumors is challenging because of their large size at presentation, peculiar location, and aggressive behavior.

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Conflicts of interest

There are no conflicts of interest.16