Two surgically cured cases of subependymoma with emphasis on magnetic resonance imaging

A Case of Lateral Ventricular Subependymoma with Intratumoral Hemorrhage <i>via</i> Neuroendoscopic Surgery

Subependymoma (SE) is a rare, usually asymptomatic, brain tumor predominantly affecting older adults and occurring in the fourth and lateral ventricles. We report a rare case of SE with intratumoral hemorrhage that could be removed by neuroendoscopy. The 81-year-old patient had been followed as an outpatient for 10 years due to an intraventricular tumor. It did not grow over the patient's lengthy follow-up. The patient was transferred to our hospital after he fainted near his home; at the time of admission, he had mild consciousness disturbance, and his Glasgow Coma Scale score was 10 points (E3V3M4). Computed tomography showed intratumoral hemorrhage and slight ventricular enlargement. Magnetic resonance (MR) imaging showed a 4 cm-sized tumor in the anterior horn of the right lateral ventricle. The lesion appeared as a mixed-intensity solid tumor and showed irregular enhancement with gadolinium. The patient underwent neuroendoscopic tumor resection on the 30^th day of the patient's hospital stay. A histopathological examination revealed small tumor cells with round nuclei scattered in the glial fibrillary background. Immunostaining was positive for glial fibrillary acidic protein; these findings are consistent with an SE diagnosis. The patient in this study had hypertension and used anticoagulants, risk factors for intratumoral hemorrhage. For intraventricular tumors with bleeding―particularly in older or more physically frail patients―minimally invasive neuroendoscopic surgery should be considered an option for tumor resection.

Multiple supratentorial subependymomas causing obstructive hydrocephalus

INTRODUCTION

Subependymomas are benign intraventricular tumours that most often occur asymptomatically and are found incidentally on autopsy. Symptomatic examples requiring surgical intervention are exceedingly rare.

CASE PRESENTATION

A 55-year-old man with no history of neurological symptoms presented with multiple episodes of loss of consciousness and increasing headaches. MRI revealed a lobulated intraventricular mass centred at the right Foramen of Monro. Obstructive hydrocephalus with localised midline shift and a second lesion were noted. Right frontal craniotomy with total removal via transcortical resection was performed.

DISCUSSION

Symptomatic subependymomas generally present with signs of hydrocephalus due to obstruction of cerebrospinal fluid pathways. There is only one other reported case of multifocal subependymomas in a symptomatic patient. An example of multiple supratentorial subependymomas causing obstructive hydrocephalus has not been previously reported.

CONCLUSIONS

Multiple subependymomas are rare. Judicious surgical management with full excision led to symptomatic improvement in our patient.

Atypical hemorrhagic presentation of a fourth ventricle subependymoma: case report

To present a case of a fourth ventricle subependymoma (SE) with a spontaneous acute subarachnoid intra-cisternal bleeding. A 33-year-old man was admitted with 5 days history of oppressive occipital headache and neck pain without additional neurological focus. Unenhanced computed tomography (CT) scan demonstrated an isointense mass located in the fourth ventricle with a spontaneously hyperdense acute extratumoral hemorrhage in the cisterna magna. Contrast-enhanced magnetic resonance imaging (MRI) revealed a well-delimitated non-enhanced tumor, hypointense on T₁-weighted and hyperintense on T_2-weighted images, involving the floor of the fourth ventricle and extending caudally into the cervical spinal canal via foramen magnum. Intraoperative, a large blood clot was removed and a macroscopically hypovascularlesion was completely excised from the right lateral recess and the floor of the fourth ventricle. Intra and postoperative immuno-histopathological examination revealed a SE. The patient has a normal postoperative course and was discharged in the fifth postoperative day. A 10-month postoperative MRI study confirmed a complete tumor resection. Symptomatic SEs should be surgically treated emphasizing the urgency in the presence of hemorrhage. The interest of this case is to demonstrate that infratentorial SEs although extremely rare, might present with acute subarachnoid bleeding.

Unusual appearance and presentation of supratentorial subependymoma in an adult patient

We report a case of a large, heterogeneously enhancing, pathologically proven, supratentorial subependymoma in a 31-year-old male patient presenting with headache, nausea and vomiting as well as gait disturbances. Although most supratentorial subependymomas have distinctive MR features, our case demonstrated imaging findings that made it indistinguishable from other more aggressive malignant supratentorial intraventricular lesions. It is of paramount importance to consider supratentorial subependymomas in the differential diagnosis of supratentorial lesions, even if their radiological features were atypical.

Spontaneous acute hemorrhage within a subependymoma of the lateral ventricle: successful emergent surgical removal through a frontal transcortical approach

INTRODUCTION. Subependymomas are benign neoplasms intimately related to the ventricular system which only exceptionally associate hemorrhagic events. We present neuroradiological and pathological evidences of intratumoral hemorrhage within a single case of subependymoma operated on at our institution. Additionally we analyze retrospectively the well-defined reports of similar cases published in the scientific literature. CASE REPORT. A 71-year-old man on anticoagulant therapy presented with abrupt and progressive deterioration of his level of consciousness. Emergent computed tomography and magnetic resonance imaging evidenced signs of acute bleeding within a mass located at the frontal horn of the left lateral ventricle, producing obstructive biventricular hydrocephalus. The lesion was immediately and completely removed through a left frontal transcortical approach. Pathological diagnosis was consistent with subependymoma displaying areas of microhemorrhage. After surgery the patient developed global anterograde and retrograde amnesia. CONCLUSIONS. A spontaneous hemorrhagic event within an asymptomatic lateral ventricle subependymoma can result in a surgical emergence as a consequence of sudden obstruction of cerebrospinal fluid pathways. Prompt and radical surgical removal of the mass, which allows a rapid resolution of hydrocephalus and prevents the risk of rebleeding, may constitute the safest management strategy.

Subependymoma in the lateral ventricle manifesting as intraventricular hemorrhage

A 32-year-old man presented with subependymoma in the lateral ventricle causing intraventricular hemorrhage and manifesting as severe headache and disturbance of consciousness. Computed tomography on admission showed a massive intraventricular hemorrhage and acute obstructive hydrocephalus. Cerebral angiography revealed no abnormal findings. Emergency external ventricular drainage was performed, and his neurological deficits gradually improved. Magnetic resonance imaging at 5 weeks after admission showed a tumor arising from the septum pellucidum or the floor of the right lateral ventricle, appearing as a mixed-intensity solid tumor, which was partially enhanced following gadolinium administration. The tumor had arisen from the septum pellucidum and was totally removed via an interhemispheric anterior transcallosal approach. Histological examination found typical subependymoma, with little vascularity. Intraventricular hemorrhage from cerebral neoplasms is usually due to highly vascular tumors. Since subependymomas are quite benign and show poor vascularity, intraventricular or subarachnoid hemorrhages are very rare, but do occasionally occur.

Subependymoma of the lateral ventricle presenting with sudden onset

A 52-year-old man presented with sudden onset of severe headache, fever, mental confusion and mild signs of left hemisphere dysfunction. Computed tomographic and magnetic resonance imaging findings suggested a preoperative diagnosis of subependymoma of the left lateral ventricle, which was subsequently confirmed by surgery. The neoplasm could be totally removed and the postoperative clinical course was favourable. The reported case is unusual because symptomatic subependymomas of the lateral ventricle are definitely rare, and almost invariably present with a progressive clinical course over a period of weeks to years.

Subependymomas: An analysis of Clinical and Imaging Features

OBJECTIVE:

Subependymomas are slow-growing, benign tumors usually found incidentally in the fourth ventricle at autopsy. They are typically associated with the ventricular system and become apparent clinically only when symptoms of hydrocephalus or mass effect develop. We review clinical, histological, and contemporary radiographic presentations of 16 subependymomas, including 2 intraparenchymal tumors.

METHODS:

We retrospectively evaluated eight patients with pathologically proven subependymomas. Initial magnetic resonance imaging and magnetic resonance spectroscopy were reviewed when available. Imaging was also available on eight outside subependymoma cases reviewed by our radiology department.

RESULTS:

Twelve of these subependymomas were intraventricular, one was in the posterior fossa, two were intraparenchymal, and one was an intramedullary spinal cord tumor. These lesions were hypo- to hyperintense on T1- and T2-weighted magnetic resonance imaging, with minimal to moderate enhancement. Initial complaints included headache, seizures, tingling sensations, and weakness. Among our eight patients who underwent gross total resection with no adjuvant therapy, no recurrences have been noted on follow-up magnetic resonance imaging.

CONCLUSION:

Subependymomas are rare, representing only 0.51% of all central nervous system tumors operated on during an 8-year period at the University of Utah. Clinical symptoms were associated with tumor location: intracranial masses caused headaches, seizures, and neurological complaints, and spinal cord locations resulted in neurological deficit. The authors review the clinical presentation, management, and contemporary radiographic appearance of this rare tumor.

Massive symptomatic subependymoma of the lateral ventricles: case report and review of the literature

Subependymomas are benign intraventricular tumors with an indolent growth pattern, which are usually asymptomatic, and most commonly occur in the fourth and lateral ventricles. When symptomatic, subependymomas often obstruct critical portions of the cerebrospinal fluid (CSF) pathway, causing hydrocephalus, and range from 3 cm to 5 cm in size. We report a case of an unusually massive subependymoma of the lateral ventricles treated with subtotal resection, ventriculoperitoneal shunt, and post-surgical radiation. The clinical course, radiographic and pathologic characteristics of this massive intraventricular subependymoma are discussed, as well as the differential diagnosis of lateral ventricular masses and a review of the literature concerning subependymomas.

201Tl-SPECT and 1H-MRS study of benign lateral ventricle tumors: differential diagnosis of subependymoma

The introduction of computed tomography (CT) and magnetic resonance (MR) imaging has resulted in the detection of increasing numbers of asymptomatic intraventricular tumors. Establishing the correct preoperative diagnosis is important to prevent unnecessary surgical intervention. Our study includes nine cases of benign lateral ventricle tumors including two cases of central neurocytoma, two of subependymal giant cell astrocytoma, two of pilocytic astrocytoma and three of subependymoma treated surgically between 1996 and 2003. MR imaging, proton MR spectroscopy ((1)H-MRS) and thallium-201 single photon emission computed tomography ((201)Tl-SPECT) were performed in all patients. All three types of tumor demonstrated heterogeneous enhancement on MR imaging with gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) and increased choline (Cho) peak and decreased N-acetyl aspartate (NAA) and creatine (Cre) peaks on (1)H-MRS. (201)Tl-SPECT showed high uptake of (201)Tl without wash out in all cases of central neurocytoma, subependymal giant cell astrocytoma and pilocytic astrocytoma, but no uptake in cases of subependymoma. Absence of (201)Tl uptake in contrast with enhancement on MR imaging and the (1)H-MRS features of modest elevation of the Cho/Cre ratio, reduction of the NAA peak and presence of lactate/lipid peaks are characteristic features of subependymomas and useful to establish a preoperative diagnosis.

A case of recurrent subependymoma with subependymal seeding: case report

Subependymoma is a rare, slow growing, rarely recurrent tumor. We report a case of re current subependymoma with subependymal seeding. An intraventricular tumor in the left temporal horn was detected in a 48-year-old female who presented with a 4-year history of dizziness and memory disturbance. Following near total surgical resection, a tumor diagnosis of subependymoma was confirmed by scattered clusters of isomorphic nuclei embedded in a dense fibrillary matrix of glial cell processes. Twenty-six months after surgery, follow-up (F/U) magnetic resonance (MR) imaging revealed tumor recurrence in the previous site which necessitated linear accelerator radiosurgery (LINAC). A further 21 months later, F/U MR imaging showed recurrent, multiple, enhanced, nodular lesions in the enlarged left lateral ventricle for which the patient underwent reoperation. Radiological and operative findings revealed local relapse with subependymal seeding. The pathological finding was similar to that of the previous tumor and compatible with subependymoma. The patient underwent radiation therapy for the residual tumor. This case history suggests that symptomatic residual tumors require close observation even though the clinical course of subependymoma is usually benign.

Clinicopathological study of seven cases of symptomatic supratentorial subependymoma

Subependymomas are rare, slow-growing tumors, the majority of which are found incidentally at postmortem examination. The authors retrospectively analyzed seven cases of symptomatic supratentorial subependymomas. Five were females and two were males, ranging in age at operation of 6-50 years (median 45). The follow-up period ranged from 1.5 to 8.3 years. Tumors were intraventricularly located as a lobulated mass with cystic changes: four in the frontal horn, two in the trigone, and one in the third ventricle. Moderate to marked enhancement was noted in two tumors of the trigone and in one tumor of the frontal horn on both CT scan and MR imaging. MR spectroscopy of a recurrent subependymoma demonstrated a higher Cho/Cr ratio of 2.66, compared with a Cho/Cr ratio (0.48) of a non-recurrent subependymoma. Angiography, which was performed in four patients, revealed no staining in two and delayed modest staining in two. Radiosurgery was performed in two patients but was ineffective. Five patients with gross total tumor resection showed no evidence of tumor recurrence to the last follow-up. The two subtotally resected trigonal tumors progressed two years after operation. No histological difference except MIB-1 index was noted between recurrent and non-recurrent cases. In conclusion, we suggest that subependymoma could show progressive biological behavior, especially in cases of markedly enhancing, irregularly contoured, large tumors located in the trigone. For symptomatic supratentorial subependymomas, gross total resection is the treatment of choice and radiation has little effect on tumor control.

From the archives of the AFIP. Cerebral intraventricular neoplasms: radiologic-pathologic correlation

Intraventricular neoplasms are readily seen on cross-sectional images, but the myriad possibilities may make a focused differential diagnosis elusive. Consideration of the tissue within and composing the ventricular lining and the clinical findings provide the means to limit the differential diagnosis when analyzing an intraventricular mass on an imaging study. Ependymomas are typically calcified, are more common in children, are more common in the fourth ventricle, and show intense enhancement on contrast-enhanced images. Subependymomas and central neurocytomas have an affinity for the anterior portion of the lateral ventricle, and both commonly demonstrate a heterogeneous cystic appearance on cross-sectional images. Subependymomas are more common in older adults, whereas central neurocytomas are more common before 40 years of age. Subependymal giant cell astrocytomas always lie near the foramen of Monro and are characterized by frequent calcification, intense enhancement on contrast-enhanced studies, and the presence of other stigmata seen in tuberous sclerosis. When a mass is centered on the choroid plexus, a highly vascular tumor-either choroid plexus papilloma, choroid plexus carcinoma, meningioma, or metastasis-should be suspected. The characteristic heavily lobulated appearance of a choroid plexus tumor favors this diagnosis over other possibilities, although it is not always possible to distinguish between the more common benign form, the choroid plexus papilloma, and the less common malignant counterpart, the choroid plexus carcinoma. By using clinical, demographic, and imaging findings, one can significantly limit the differential diagnosis for many of the most common intraventricular neoplasms.

Symptomatic subependymomas of the lateral ventricles. Report of eight cases

Subependymomas are rare, slow-growing, benign intraventricular tumors, which often are asymptomatic and are discovered incidentally. The review of the literature shows more than 100 symptomatic cases, less than half located in the lateral ventricles. Here we report 8 cases of symptomatic subependymomas of the lateral ventricles, studied by CT and/or MR and treated by direct surgical approach. The suspicion of a subependymoma should arise when a patient older than 10-15 years with long clinical history presents an intraventricular tumor isodense on CT and isointense in T1 and hyperintense in T2 on MR, with scarce or discrete contrast enhancement. Surgical treatment is indicated in symptomatic subependymomas of the lateral ventricles and usually allows complete tumor removal. The prognosis is usually good, also without postoperative irradiation.

MRI of intracranial subependymoma: report of a case

Subependymoma is a rare, benign intraventricular tumour and a case of septum pellucidum origin examined with CT and MR is reported. Well demarcated non-enhancing mass with multiple small intratumoral cysts is demonstrated on CT and MR images. The differential diagnosis from ependymoma has some therapeutic implications but may not be possible by CT or MRI.

Hemorrhage in a highly vascularized subependymoma of the septum pellucidum: case report

A 63-year-old man was admitted to our hospital because of loss of memory, disorientation, nausea, and urinary incontinence. Cerebral computed tomographic and magnetic resonance imaging scans revealed a tumor with intratumoral hemorrhage affecting the corpus callosum and the septum pellucidum. A partial resection of the tumor was performed, but the patient died the next day from an episode of bleeding. Postmortem examination revealed a highly vascularized subependymoma with acute bleeding in the tumor and in the surrounding brain parenchyma. The importance of considering a highly vascularized subependymoma is noted when a tumor related to the ventricular system is diagnosed.