RESUMO
Colloid cysts are typically slow-growing lesions that account for approximately 1% of primary intracranial neoplasms and predominantly exist intraventricularly. These benign lesions typically can exist symptom-free for years and do not require surgical intervention. However, if the location of the colloid cyst is symptomatic, surgical debulking may be indicated. In this intraoperative video, we illustrate the case of an 8 cm, intra/extra-ventricular colloid cyst that appeared as a craniopharyngioma on preoperative imaging, but upon resection via a trans-middle temporal gyrus approach, was found to be very atypically filled with a thick, "tarry" substance, which we hypothesize is due to serial, subacute lesional hemorrhages. After debulking and piecemeal resection of the majority of the mass with ultrasonic aspiration and microsurgical tools, a hard, calcified nodule was left tenaciously adherent to the superior cerebellar artery to prevent damage to this vascular structure.
Assuntos
Neoplasias do Ventrículo Cerebral/cirurgia , Cistos Coloides/cirurgia , Eosinofilia/cirurgia , Microcirurgia/métodos , Neoplasias do Ventrículo Cerebral/diagnóstico por imagem , Neoplasias do Ventrículo Cerebral/etiologia , Cistos Coloides/diagnóstico por imagem , Cistos Coloides/etiologia , Diagnóstico Diferencial , Eosinofilia/complicações , Eosinofilia/diagnóstico por imagem , Feminino , Humanos , Macrófagos/patologia , Pessoa de Meia-IdadeAssuntos
Neoplasias do Ventrículo Cerebral/diagnóstico , Quarto Ventrículo , Linfoma de Células B/diagnóstico , Neoplasias do Ventrículo Cerebral/etiologia , Neoplasias do Ventrículo Cerebral/terapia , Feminino , Humanos , Linfoma de Células B/etiologia , Linfoma de Células B/terapia , Pessoa de Meia-IdadeRESUMO
Central neurocytomas are rare benign tumors of the central nervous system that are typically located in the lateral ventricles. Since they were first reported in the early 1980s, many advancements have been made in terms of their diagnosis and treatment. Despite the progress made, the origin of these rare tumors and effective newer treatment strategies remain elusive. Central neurocytomas represent 0.1-0.5% of all primary brain tumors. Since they are typically intraventricular, these tumors tend to present clinically with hydrocephalus. CT scanning and MRI are useful in localizing these tumors; however, due to their numerous ambiguous features, the ultimate diagnosis relies on immunohistochemistry and electron microscopy studies of sampled tissue. Currently, surgical removal with a gross-total resection of these tumors is the treatment of choice. Various radiotherapy techniques, including both conventional radiotherapy and stereotactic radiosurgery, have been shown to be useful in cases of residual tumor after sub-total resection and tumor recurrence. The benign nature of these tumors tends to offer a favorable outcome for most patients; however, recurrence rates are relatively high and tumors with high-grade features or extraventricular location tend to have a less favorable prognosis. We present a comprehensive review of these rare tumors, including their epidemiology, clinical presentation, radiological presentation, histopathological findings, and options for intervention including surgery, radiation therapy, stereotactic radiosurgery, and chemotherapy.
Assuntos
Neoplasias Encefálicas , Neoplasias do Ventrículo Cerebral , Neurocitoma , Animais , Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/etiologia , Neoplasias Encefálicas/terapia , Neoplasias do Ventrículo Cerebral/diagnóstico , Neoplasias do Ventrículo Cerebral/etiologia , Neoplasias do Ventrículo Cerebral/terapia , Humanos , Neurocitoma/diagnóstico , Neurocitoma/etiologia , Neurocitoma/terapia , Radiocirurgia/métodos , Resultado do TratamentoRESUMO
Meningiomas are among the most common brain tumors in adults. They are most commonly located over the cerebral convexities and are infrequently found in an intraventricular location. Ionizing cranial radiation is a risk factor for late occurrence of meningiomas within the radiation field. While pathologic grading of meningiomas is straightforward, significant variability often exists between pathologists in applying standard grading criteria. This has implications for prognosis. Radiation-induced meningiomas may also have predilection to recur. The authors describe a case of an intraventricular meningioma occurring 23 years after cranial irradiation for childhood acute lymphoblastic leukemia.
Assuntos
Neoplasias do Ventrículo Cerebral/etiologia , Neoplasias do Ventrículo Cerebral/patologia , Neoplasias Meníngeas/etiologia , Neoplasias Meníngeas/patologia , Meningioma/etiologia , Meningioma/patologia , Neoplasias Induzidas por Radiação/patologia , Adulto , Neoplasias do Ventrículo Cerebral/diagnóstico , Pré-Escolar , Diagnóstico Diferencial , Humanos , Masculino , Neoplasias Meníngeas/diagnóstico , Meningioma/diagnóstico , Neoplasias Induzidas por Radiação/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/radioterapiaRESUMO
BACKGROUND: Intraventricular oligodendroglioma remains a rare diagnosis, with high-grade/anaplastic IVO being an even rarer subtype. These lesions vary in regard to tumor grading and clinical presentation, as compared with their intraparenchymal counterparts. A case report and review of the previous literature regarding IVO and tumor grading were conducted. CASE DESCRIPTION: A case report of a patient with an anaplastic oligodendroglioma confined entirely within the ventricular system is presented. The patient underwent gross total surgical resection with perioperative shunt placement, yet developed aggressive recurrence of disease. The literature regarding the clinical presentation, methodology of diagnosis, and treatment of IVO was reviewed. Thirty-three studies reporting 70 patients with IVO were identified in the literature. Only 2 previous case reports of high-grade/anaplastic IVO were identified. Accurate diagnosis of these lesions, including immunohistochemistry, electron microscopy, and molecular/chromosomal subtyping, is imperative. Surgical resection with frequent perioperative shunting, as well as chemotherapy, remains the mainstay of therapy. Adjuvant therapies may differ significantly according to the tumor grade and molecular subtype. CONCLUSIONS: Intraventricular oligodendroglioma remains an infrequently encountered lesion, yet is usually found to be low grade at the time of surgery. Anaplastic IVO is an exceedingly rare lesion, with only 3 case reports in the literature. Future therapy for these aggressive lesions may be based on susceptibility to various chemotherapeutic agents according to molecular subtyping.
Assuntos
Neoplasias do Ventrículo Cerebral/diagnóstico , Neoplasias do Ventrículo Cerebral/cirurgia , Oligodendroglioma/diagnóstico , Oligodendroglioma/cirurgia , Neoplasias do Ventrículo Cerebral/etiologia , Feminino , Humanos , Oligodendroglioma/etiologia , Adulto JovemAssuntos
Doença de Alexander/complicações , Doença de Alexander/epidemiologia , Neoplasias do Ventrículo Cerebral/etiologia , Mioclonia/etiologia , Músculos Palatinos , Adulto , Idade de Início , Doença de Alexander/diagnóstico , Neoplasias do Ventrículo Cerebral/diagnóstico , Feminino , Humanos , Imageamento por Ressonância MagnéticaRESUMO
We report a case of jugular foramen schwannoma associated with tuberous sclerosis. A 28-year-old female with tuberous sclerosis presented to Hikone Municipal Hospital with subacute onset of somnolence, ataxic gait and frequent vomiting. Her tuberous sclerosis was diagnosed at the age of 9, when she developed hydrocephalus caused by subependymal giant cell astrocytoma near the foramen of Monro, which was treated by surgical resection and VP shunt placement followed by radiation and chemotherapy. Brain MR images revealed a 3 cm enhancing mass extending from the left jugular foramen to the cerebellopontine cistern, accompanied by perifocal edema of the brain stem and cerebellar hemisphere. The tumor was partially removed via suboccipital craniotomy and histologically diagnosed as a schwannoma. After surgery her symptoms promptly improved and 4 months later she underwent additional stereotactic radiosurgery. No tumor regrowth has been observed at 94 months. Intracranial schwannoma complicating tuberous sclerosis is very rare. Only one other case has been reported in the literature.
Assuntos
Veias Jugulares , Neoplasias Primárias Múltiplas , Neurilemoma/etiologia , Esclerose Tuberosa/complicações , Neoplasias Vasculares/etiologia , Adulto , Astrocitoma/etiologia , Astrocitoma/terapia , Neoplasias do Ventrículo Cerebral/etiologia , Neoplasias do Ventrículo Cerebral/terapia , Ventrículos Cerebrais , Feminino , Humanos , Hidrocefalia/etiologia , Neurilemoma/diagnóstico , Neurilemoma/cirurgia , Resultado do Tratamento , Neoplasias Vasculares/diagnóstico , Neoplasias Vasculares/cirurgiaRESUMO
BACKGROUND: Intracranial dissemination of pituitary adenomas is a rare event that does not equate malignancy. Most of the cases have been reported as metastases from pituitary carcinoma. A case of papillary pituitary carcinoma developed 12 years after radiotherapy for prolactin-secreting hormone pituitary adenoma is presented. CASE DESCRIPTION: A 37-year-old woman was admitted for the second time with neurologic disturbance and hypertension. A gadolinium-enhanced magnetic resonance scan of the brain demonstrated a 50-mm enhanced mass (absent on previous studies) on the lateral ventricle, involving the left temporal lobe. The patient underwent a craniotomy and biopsy of the lesion that was consistent with pituitary carcinoma; it was immunoreactive to follicle-stimulating hormone, adrenocorticotropic hormone, pituitary tumor-transforming gene, and epithelial cell adhesion molecule. Transmission electron microscopy analysis confirmed the secretory pituitary tumor diagnosis. CONCLUSIONS: The tumor was considered a primary pituitary papillary carcinoma. The clinical course indicated that this tumor was the seedling of a pituitary tumor, although it could be interpreted as metastases from a pituitary carcinoma.
Assuntos
Carcinoma Papilar/diagnóstico , Neoplasias do Ventrículo Cerebral/diagnóstico , Segunda Neoplasia Primária/diagnóstico , Neoplasias Hipofisárias/diagnóstico , Prolactinoma/diagnóstico , Radioterapia/efeitos adversos , Adulto , Biomarcadores Tumorais/metabolismo , Carcinoma Papilar/etiologia , Carcinoma Papilar/terapia , Neoplasias do Ventrículo Cerebral/etiologia , Neoplasias do Ventrículo Cerebral/terapia , Diagnóstico Diferencial , Progressão da Doença , Evolução Fatal , Feminino , Humanos , Lactotrofos/patologia , Lactotrofos/efeitos da radiação , Ventrículos Laterais/patologia , Invasividade Neoplásica , Neoplasia Residual , Segunda Neoplasia Primária/etiologia , Segunda Neoplasia Primária/terapia , Hipófise/metabolismo , Hipófise/patologia , Hipófise/efeitos da radiação , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/terapia , Prolactinoma/complicações , Prolactinoma/terapia , Tempo , Fatores de TempoRESUMO
UNLABELLED: A glioblastoma presenting as a solitary third ventricle mass is exceptional. CASE DESCRIPTION: We report the case of a 29-year-old woman who lost consciousness, was taken to hospital and referred a previous history of depression and diabetes insipidus. Magnetic resonance imaging study revealed a heterogeneous anterior third ventricle mass with ring enhancement after contrast administration. It was approached and subtotally resected by a transcortical-transventricular route and histological diagnosis proved it to be a glioblastoma. There are only two other similar well-described cases and another nine have been previously reported in surgical series of high grade gliomas and glioblastomas. The possible origin of this lesion is discussed.
Assuntos
Neoplasias do Ventrículo Cerebral/diagnóstico , Neoplasias do Ventrículo Cerebral/cirurgia , Glioblastoma/diagnóstico , Glioblastoma/cirurgia , Terceiro Ventrículo , Adulto , Neoplasias do Ventrículo Cerebral/etiologia , Feminino , Glioblastoma/etiologia , HumanosRESUMO
In the central nervous system, tuberous sclerosis complex (TSC) is characterized by a range of lesions including cortical tubers, white matter heterotopias, subependymal nodules, and subependymal giant cell astrocytomas (SEGAs). Recent studies have implicated an important role for the TSC genes TSC1 and TSC2, in a signaling pathway involving the mammalian target of rapamycin (mTOR) kinase. We performed immunohistochemical and genetic analyses on SEGAs from 7 TSC patients, 4 with mutations in TSC1, and 3 with mutations in TSC2. SEGA cells show high levels of phospho-S6K, phospho-S6, and phospho-Stat3, all proteins downstream of and indicative of mTOR activation. Such expression is not seen in histologically normal control tissue. Five of 6 SEGAs also showed evidence of biallelic mutation of TSC1 or TSC2, suggesting that SEGAs develop due to complete loss of a functional tuberin-hamartin complex. We conclude that TSC SEGAs likely arise through a two-hit mechanism of biallelic inactivation of TSC1 or TSC2, leading to activation of the mTOR kinase.
Assuntos
Astrocitoma/etiologia , Neoplasias do Ventrículo Cerebral/etiologia , Regulação da Expressão Gênica , Ventrículos Laterais , Proteínas Quinases/genética , Esclerose Tuberosa/complicações , Esclerose Tuberosa/genética , Adolescente , Alelos , Astrocitoma/genética , Astrocitoma/metabolismo , Neoplasias do Ventrículo Cerebral/genética , Neoplasias do Ventrículo Cerebral/metabolismo , Criança , Pré-Escolar , Proteínas de Ligação a DNA/metabolismo , Feminino , Inativação Gênica , Genes Supressores de Tumor , Humanos , Perda de Heterozigosidade , Masculino , Mutação , Fosforilação , Proteínas Quinases/metabolismo , Proteínas/genética , Proteínas Repressoras/genética , Proteína S6 Ribossômica/metabolismo , Proteínas Quinases S6 Ribossômicas/metabolismo , Fator de Transcrição STAT3 , Transdução de Sinais , Serina-Treonina Quinases TOR , Transativadores/metabolismo , Proteína 1 do Complexo Esclerose Tuberosa , Proteína 2 do Complexo Esclerose Tuberosa , Proteínas Supressoras de TumorRESUMO
Five cases of intraventricular subependymal giant cell astrocytomas (SEGCA) were retrospectively reviewed. Records and detailed work-up of all five cases were well maintained in view of rare occurrence of these tumors. The five patients were males aged 10, 12 (2 cases), 14 and 18 years. The 18-year-old aged male had no stigmata of tuberous sclerosis (TSC) on examination, while the rest presented with features of TSC, intraventricular tumors and hydrocephalus. None of the five cases had renal tumors and did not reveal cardiac tumors. Skin manifestations like shagreen patches were present in two, facial angiofibromas in three, periungal fibromas in two, hypopigmented macules in two and ash-leaf spot in two patients. Fundoscopic examination revealed retinal astrocytomas in two cases only. Two of the five children did not have mental compromise. A child who started throwing seizures early (at 5 months of age) had severe mental retardation. Although SEGCA is a less vascular tumor, one tumor bled profusely intraoperatively; it was excised rapidly via the transcortical route to salvage the life of the child, though he was planned for the transcallosal route like the other cases. The tumor of another child was also very vascular. Four children survived surgery and required no shunt CSF diversion, while one died of severe ventriculitis and septicemia 3 weeks after surgery.
Assuntos
Astrocitoma/diagnóstico , Astrocitoma/cirurgia , Neoplasias do Ventrículo Cerebral , Neoplasias do Ventrículo Cerebral/diagnóstico , Neoplasias do Ventrículo Cerebral/cirurgia , Adolescente , Astrocitoma/etiologia , Neoplasias do Ventrículo Cerebral/etiologia , Criança , Humanos , Masculino , Prognóstico , Esclerose Tuberosa/complicaçõesRESUMO
PATIENT: We report on an unusual case of a recurrent and progressive spinal pilocytic astrocytoma with metastatic spreading to the hypothalamus in a 14-year-old boy. TREATMENT AND RESULTS: The patient underwent resection of an intramedullary atypical pilocytic astrocytoma classified as WHO grade II at the level of Th11/12 in 1997 and received local photon beam irradiation. Three years later, a second operation was necessary for a recurrent tumour at the same level. Seventeen months later, a second recurrent tumour with spinal seeding as well as an intracranial tumour in the third ventricle and hypothalamus was detected. He was shunted for an occlusive hydrocephalus and a stereotactic biopsy of the hypothalamic lesion was performed. The tumour was classified as anaplastic pilocytic astrocytoma (WHO grade III). He received chemotherapy with ifosfamide, cisplatin and etoposide (HIT-GBM-C-protocol), craniospinal radiation, and is still alive 60 months after the first operative intervention without neurological deficits.
Assuntos
Astrocitoma/complicações , Neoplasias do Ventrículo Cerebral/etiologia , Neoplasias Hipotalâmicas/etiologia , Neoplasias da Medula Espinal/complicações , Adolescente , Astrocitoma/patologia , Astrocitoma/cirurgia , Astrocitoma/terapia , Encéfalo/patologia , Terapia Combinada , Humanos , Imageamento por Ressonância Magnética , Masculino , Neoplasias da Medula Espinal/patologia , Neoplasias da Medula Espinal/cirurgia , Neoplasias da Medula Espinal/terapia , Tomografia Computadorizada por Raios XRESUMO
We describe two cases of central neurocytoma in the lateral ventricle. Ultrastructural examination showed occasional cilia mixed in with sparse dense core vesicles and thin tumor cell processes containing parallel microtubules. These central neurocytomas revealed evidence of ependymal differentiation. We propose that central neurocytoma originates from multiple differentiation from the germinal matrix cell layer.
Assuntos
Neoplasias do Ventrículo Cerebral/ultraestrutura , Neurocitoma/ultraestrutura , Adulto , Diferenciação Celular , Neoplasias do Ventrículo Cerebral/etiologia , Epêndima/ultraestrutura , Humanos , Masculino , Microscopia Eletrônica , Neurocitoma/etiologiaRESUMO
Malignant fibrous histiocytoma is a rare intracranial neoplasm. It usually presents as a meningeal mass but occurs also intraaxially. Few information is available on cellular origin, premalignant histologic stages and time course of malignant transformation. We report a case of a primary intraventricular malignant fibrous histiocytoma in a patient who five years prior to clinical manifestation of the malignancy was found to have an intraventricular mass with benign CT characteristics.
Assuntos
Neoplasias do Ventrículo Cerebral/etiologia , Neoplasias do Ventrículo Cerebral/patologia , Histiocitoma Fibroso Benigno/etiologia , Histiocitoma Fibroso Benigno/patologia , Neoplasias Encefálicas/patologia , Progressão da Doença , Humanos , Ventrículos Laterais/patologia , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios XRESUMO
Intraparenchymal pericatheter cyst is rarely reported. Obstruction in the ventriculoperitoneal shunt leads to recurrence of hydrocephalus, signs of raised intracranial pressure and possibly secondary complications. Blockage of the distal catheter can result, unusually, in cerebrospinal fluid oedema and/or intraparenchymal cyst around the ventricular catheter which may produce focal neurological deficit. We report two cases of distal catheter obstruction with formation of cysts causing local mass effect and neurological deficit. Both patients had their shunt system replaced, which led to resolution of the cyst and clinical improvement. One patient had endoscopic exploration of the cyst which confirmed the diagnosis made on imaging studies. Magnetic resonance imaging was more helpful than computed tomography in differentiating between oedema and collection of cystic fluid. Early recognition and treatment of pericatheter cyst in the presence of distal shunt obstruction can lead to complete resolution of symptoms and signs.
Assuntos
Cistos do Sistema Nervoso Central/etiologia , Neoplasias do Ventrículo Cerebral/etiologia , Hidrocefalia/cirurgia , Derivação Ventriculoperitoneal/efeitos adversos , Cistos do Sistema Nervoso Central/diagnóstico , Neoplasias do Ventrículo Cerebral/diagnóstico , Criança , Falha de Equipamento , Humanos , Imageamento por Ressonância Magnética , Masculino , Derivação Ventriculoperitoneal/instrumentaçãoRESUMO
Primary intracranial rhabdomyosarcoma is extremely rare. Here, a case that is most consistent with a botryoid rhabdomyosarcoma is described in a 4.5-year-old boy. The case is unique because it was preceded by a congenital Dandy-Walker malformation, choroid plexus hyperplasia and an enormous oversecretion of cerebrospinal fluid during infancy.
Assuntos
Neoplasias do Ventrículo Cerebral/patologia , Plexo Corióideo/patologia , Plexo Corióideo/cirurgia , Rabdomiossarcoma/patologia , Encefalopatias/patologia , Encefalopatias/cirurgia , Neoplasias do Ventrículo Cerebral/etiologia , Pré-Escolar , Humanos , Hiperplasia/complicações , Hiperplasia/patologia , Hiperplasia/cirurgia , Masculino , Rabdomiossarcoma/etiologiaAssuntos
Neoplasias do Ventrículo Cerebral/etiologia , Glioma/etiologia , Esclerose Tuberosa/complicações , Adulto , Neoplasias do Ventrículo Cerebral/diagnóstico , Neoplasias do Ventrículo Cerebral/cirurgia , Feminino , Glioma/diagnóstico , Glioma/cirurgia , Humanos , Intensificação de Imagem Radiográfica , Tomografia Computadorizada por Raios X , Esclerose Tuberosa/diagnósticoRESUMO
Tuberous sclerosis (TS) is well known to be occasionally associated with subependymal giant cell astrocytoma (SGCA). SGCA is considered to be a benign tumor in its clinical course and morphology. However, this tumor is grown sometimes so rapid and caused hydrocephalus. To our knowledge, little is known about hemocirculation and metabolism, particularly in relation with proliferating activity of TS and SGCA. We measured hemocirculation and metabolism of SGCA developed in a case of TS using positron emission tomography (PET). A 13-year-old-boy who had frequently developed convulsions four months after birth. He was diagnosed as TS and had been medically treated with anticonvulsants, since multiple intraventricular calcifications were detected by CT, at the age of five months. The convulsions had been well controlled. In March 1993, he presented with syncopal attack and admitted to our hospital. CT showed multiple subependymal nodules. Among the nodules, one of the left anterior horn exceeded 2cm in size obliterated Monro's foramen. The tumor was homogeneously enhanced with contrast medium. The lesion detected by postcontrast T1-weighted MR imaging had almost the same status as that by CT. T2-weighted image revealed cortical tubers as high intensity area at the left frontal and parietooccipital regions. PET was performed with the Headtome IV. Hemocirculation of the tumor was lower than that of contralateral gray matter, which suggested poor blood supply. The oxygen and glucose metabolism of the tumor were decreased compared with contralateral gray matter, indicative of a low activity of proliferation and a clinically benign tumor in the present case.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Neoplasias do Ventrículo Cerebral/diagnóstico por imagem , Glioma/diagnóstico por imagem , Esclerose Tuberosa/complicações , Adolescente , Encéfalo/metabolismo , Neoplasias do Ventrículo Cerebral/etiologia , Neoplasias do Ventrículo Cerebral/metabolismo , Glioma/etiologia , Glioma/metabolismo , Glucose/metabolismo , Humanos , Masculino , Tomografia Computadorizada de EmissãoRESUMO
A 20-year-old man received 60 Gy of radiation therapy after partial removal of craniopharyngioma. The patient had been well and follow-up CT scans did not show any aggravation for 16 years. Since his activity gradually diminished, he underwent an MRI at the age of 36 which revealed an abnormal mass on the corpus callosum. The mass lesion progressively enlarged thereafter, and was diagnosed as anaplastic astrocytoma by a stereotactic biopsy. He was treated with interferon, however, died at the age of 37. Review of literature disclosed 19 other cases of glioma following radiation therapy for sellar/parasellar tumors. Characteristic features of these cases included 1) lowness of age compared to common glioma cases, 2) tendency to be malignant, 3) tendency to occur in areas where significant doses of radiation had been received previously.
Assuntos
Neoplasias do Ventrículo Cerebral/etiologia , Craniofaringioma/radioterapia , Glioblastoma/etiologia , Neoplasias Induzidas por Radiação , Segunda Neoplasia Primária , Neoplasias Hipofisárias/radioterapia , Radioterapia/efeitos adversos , Adulto , Humanos , MasculinoRESUMO
We report an unusual case of inflammatory pseudotumor of the choroid plexus of the right lateral ventricle, manifesting as an intraventricular mass and causing unilateral hydrocephalus in a 48-year-old man who suffered from Sjögren's disease and subacute cutaneous lupus erythematosus. The lesion obliterated the normal choroidal architecture by a mixed chronic inflammatory process that was associated with reactive connective tissue changes. Immunohistochemical studies showed no light-chain restriction in the cells, and residual islands of transthyretin-positive epithelial cells were identified, implicating the choroid plexus origin of the mass.