Dysembryoplastic neuroepithelial tumor-like neoplasm of the septum pellucidum: a lesion often misdiagnosed as glioma: report of 10 cases

The authors report a series of 10 low-grade neoplasms arising in the midline anteriorly in the region of the septum pellucidum with many of the histologic features of dysembryoplastic neuroepithelial tumor (DNT). The patients (five female, five male) ranged in age from 6 to 35 years (mean age, 21.5 years). The most common presenting symptoms were headache, nausea and vomiting, and visual disturbances. Radiographically, the tumors extended into the lateral ventricles from the septal region and obstructed the foramen of Monro. Varying degrees of hydrocephalus were present. The lesions were lobular, well-delineated, hypointense to brain on T1-weighted magnetic resonance imaging, and hyperintense on T2-weighted images. They were uniformly nonenhancing or showed only minimal peripheral enhancement. The tumors, in aggregate, had the histologic features of DNT. These included a mucin-rich background, oligodendrocyte-like cells, "floating neurons," and a "specific glioneuronal element." Seven patients underwent gross total resection and two underwent subtotal resection. No patients received adjuvant chemotherapy or radiotherapy. On follow-up (n = 6; median, 14 months), all tumors had either not recurred or were radiologically stable. On the basis of both neuroimaging and histopathology, DNT-like lesions should be considered in the differential diagnosis of midline intraventricular tumors in children and young adults. Distinction from more aggressive neoplasms is essential because these tumors appear to behave in a benign fashion.     

Electroencephalography-guided resection of dysembryoplastic neuroepithelial tumor: case report

A 3-year-old girl presented with a dysembryoplastic neuroepithelial tumor in the right cingulate gyrus manifesting as epilepsy refractory to anticonvulsant medication. Computed tomography and magnetic resonance imaging revealed a cystic tumor in the right cingulate gyrus. The tumor was removed under intraoperative electrocorticography guidance. Abnormal spikes recorded adjacent to the tumor disappeared immediately after total removal. Histological examination showed a multinodular, multicystic structure, satisfying the criteria for the diagnosis of dysembryoplastic neuroepithelial tumor. She has remained seizure-free for more than 4 years without complications. In this case, intraoperative electrocorticography was very useful to identify the possible focus and prevent unnecessary resection of the adjacent tissue. Total removal of the tumor resulted in a dramatic reduction of seizure activity.     

Infratentorial localisation of a dysembryoplastic neuroepithelial tumor. A case report

Neuroepithelial dysembryoplastic tumor (DNT) is usually considered as a supratentorial benign neoplasm. DNT of the posterior fossa is a very rare entity and only four previous cases were reported in the literature. We describe a case of a 26-Year-old woman presenting recurrent episodes of vertigo. Magnetic resonance imaging revealed four cystic lesions located in the cerebellum, hypointense on T1-weighted images and hyperintense on T2-weighted images, without gadolinium enhancement. After partial resection, histological examination showed small glial cells, oligodendrocytes-like, lying in an eosinophilic alveolar matrix with some floating neurons. Due to this specific glioneuronal element, the diagnosis of DNT was retained. We discuss the clinical and radiological particularities of this infratentorial location and compare our case with those previously described in the literature.     

Choriocarcinoma of the septum pellucidum: Case report

A case of choriocarcinoma of the septum pellucidum is presented. The patient, a 6-year-old boy, demonstrated high levels of human chorionic gonadotropin in his urine, serum, and cerebrospinal fluid, and precocious puberty. The physical conditions and laboratory data returned to normal after surgical removal of the tumor, whole brain irradiation, and chemotherapy. Currently, there is no evidence of recurrence at 5 months after surgery.     

Endodermal cyst of septum pellucidum and pregnancy: a case report

BACKGROUND

Endodermal or Neurenteric cysts are commonly found in spine. Their intracranial occurrence is rare and such a cyst in the septum pellucidum is exceptional.

METHOD

We report a woman, with 33 week pregnancy, presenting in a semiconscious state due to raised intracranial pressure (ICP) due to hydrocephalus caused by a large lesion in the septum pellucidum. Computed tomography (CT) revealed the lesion which was better characterised by the Magnetic Resonance Imaging (MRI). First baby was delivered by LSCS and bilateral ventriculo-peritoneal shunts were inserted; and later on the cyst was excised.

RESULT

There was full neurological recovery following the insertion of VP shunt. After excision of cyst cerebrospinal fluid (CSF) pathway was established and shunts could be removed. Post-operative period was complicated by septic ventriculitis. Eventually patient was discharged home in excellent condition.

CONCLUSION

Endodermal cyst of septum pellucidum is an uncommon condition. Such lesions may be large when revealed, good outcome is expected after surgical excision.     

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.     

Malignant transformation of a dysembryoplastic neuroepithelial tumor. Case report

A 29-year-old man presented in 1984 with a recent onset of partial seizures marked by speech arrest. Electroencephalography identified a left frontotemporal dysrhythmia. Computerized tomography (CT) scanning revealed a superficial hypodense nonenhancing lesion in the midleft frontal convexity, with some remodeling of the overlying skull. The patient was transferred to the London Health Sciences Centre for subtotal resection of what was diagnosed as a "fibrillary astrocytoma (microcystic)." He received no chemotherapy or radiation therapy and remained well for 11 years. The patient presented again in late 1995 with progressive seizure activity. Both CT and magnetic resonance imaging demonstrated a recurrent enhancing partly cystic lesion. A Grade IV astrocytoma was resected, and within the malignant tumor was a superficial area reminiscent of a dysembryoplastic neuroepithelial tumor (DNT). Data on the lesion that had been resected in 1984 were reviewed, and in retrospect the lesion was identified as a DNT of the complex form. It was bordered by cortical dysplasia and contained glial nodules, in addition to the specific glioneuronal element. The glial nodules were significant for moderate pleomorphism and rare mitotic figures. The Ki67 labeling index averaged 0.3% in the glial nodules and up to 4% focally. Cells were rarely Ki67 positive within the glioneuronal component. This case is the first documented example of malignant transformation of a DNT. It serves as a warning of the potential for malignant transformation in this entity, which has been traditionally accepted as benign. This warning may be especially warranted when confronted with complex forms of DNT. The completeness of resection in the benign state is of paramount importance.     

A case of cavernous angioma at the septum pellucidum

A 35-year-old female presented with a cavernous angioma of the septum pellucidum manifesting as headache and nausea. Computed tomography and magnetic resonance imaging revealed a mass at the septum pellucidum with intraventricular hemorrhage and mild hydrocephalus. Digital subtraction angiography showed no abnormal finding and thallium-201 single photon emission computed tomography showed no uptake in the lesion. The preoperative diagnosis was intraventricular tumor, such as subependymoma. The lesion was completely resected through the transcallosal approach. The histological diagnosis was cavernous angioma. Cavernous angiomas are usually located in the cerebral parenchyma and rarely occur in the cerebral ventricles. In particular, cavernous angioma at the septum pellucidum is very rare. If magnetic resonance imaging does not clearly show the typical peripheral hypointense rim, neuroimaging diagnosis will be difficult. Surgical resection should be considered to confirm the histopathology, in particular if bleeding and hydrocephalus are present.     

Subependymoma of the septum pellucidum radiologically indistinguishable from cavernous angioma--case report

A case of subependymoma of the septum pellucidum in a 54-year-old female is presented. Computed tomography and magnetic resonance imaging revealed a partially calcified mass with intratumoral hematomas, and cerebral angiograms disclosed a relatively hypovascular lesion. Preoperatively, a cavernous angioma was suspected. The tumor was removed, and histological examination proved it to be a subependymoma containing a fine fibrillary matrix. On immunohistochemical analysis, both the matrix and the tumor cells were positive for glial fibrillary acidic protein staining.     

胚胎发育不良性神经上皮瘤的诊治

目的探讨胚胎发育不良性神经上皮瘤（DNT）的诊断和治疗。方法2001年11月至2005年2月共收治DNT患者18例。对临床表现、影像学检查、术前诊断、治疗及病理作回顾性分析。结果癫痫为主要临床表现;磁共振成像（MRI）为无占位效应的病变;病理上特异性胶质神经元和多发结节为其特点;外科手术治疗,癫痫控制良好。结论DNT为良性病变,需外科治疗,手术时全切除肿瘤及术中采用皮层脑电图监护可提高手术疗效。     

Primary oligodendroglioma of the septum pellucidum

The oligodendroglioma is an infrequent cerebral tumor of glial ancestry. It is even rarer when primarily arising within the confines of the ventricles and particularly if originating from the septum pellucidum. A 22-year-old man harboring a primary oligodendroglioma of the septum pellucidum was successfully treated by intraventricular tumor removal through a left transcortical-transventricular approach, using microsurgical technique. A brief review of relevant data about both intraventricular oligodendrogliomas and tumors of the septum pellucidum is presented.