| Findings: |
5/28/03 MRI 1. Large right cerebellar intra-axial solid and cystic mass with peripheral ring enhancement of the cyst and adjacent edema.
| Discussion: |
Gangliogliomas account for 0.4%–0.9% of all intracranial neoplasms and 1%–4% of all pediatric neoplasms of the CNS. Most (80%) occur in patients younger than 30 years with a peak age of incidence between 10 and 20 years. They may manifest in newborns with or without neurologic impairment and are slightly more common in males. There is a distinct predilection for the cerebral hemispheres, especially the temporal lobe. The majority occurred in the temporal lobe (38%), followed by the parietal lobe (30%) and the frontal lobe (18%). Numerous other locations have been reported, including the brainstem, cerebellum, pineal region, spinal cord, optic nerve, optic chiasm, and ventricles. A case of a ganglioglioma attached to the septum pellucidum within the lateral ventricle with an imaging appearance virtually identical to that of a subependymoma or central neurocytoma has been reported. Gangliogliomas of the temporal lobe are commonly associated with the clinical presentation of medically refractory seizures, particularly those of the partial complex type. These tumors are the most common cause (40%) of chronic temporal lobe epilepsy. Clinical associations include several reports in the literature of "hemifacial spasm" in combination with a cerebellar ganglioglioma occurring in infants and one case report of coexisting ganglioglioma and Rasmussen encephalitis in the same cerebral hemisphere. Rare locations for gangliogliomas include the pineal region and the ventricular system.
Gangliogliomas share many imaging features with other low-grade neoplasms. Cross-sectional imaging studies reveal a solid mass (43%), a cystic mass (5%), or a solid-cystic combination (52%) that is typically located in the periphery of a cerebral hemisphere. Calcification is a common finding. Reflecting a generally benign biologic nature, there is usually little associated mass effect or evidence of surrounding vasogenic edema. Gangliogliomas that occur in children tend to have greater overall tumor volume (average: eight times larger) than those arising in adults. Gangliogliomas have variable manifestations at nonenhanced CT. A hypoattenuating mass is the most frequent manifestation (38%), followed by a mixed attenuation mass (32%) and an isoattenuating mass (15%) or hyperattenuating mass (15%) Calcification is less commonly seen in association with solid-appearing lesions .Remodeling of the skull may be seen if the neoplasm is located within the peripheral brain. Occasionally, the neoplasm may be completely undetectable at CT. The frequency of enhancement following intravenous administration of iodinated contrast media is variable, occurring in 16%–80% of gangliogliomas. The MR imaging appearance of gangliogliomas is also variable and nonspecific. In general, the lesions are hypointense to isointense relative to gray matter on T1 images and hyperintense relative to gray matter on T2 imaging. The solid-appearing components have an even more variable presentation at imaging. Some tumors may manifest as a hyperintense mass on T1-weighted images. They commonly have at least some regions of high signal intensity on T2-weighted images . Not all gangliogliomas are truly cystic despite a cystlike appearance, and the term cystic should be reserved for those that demonstrate a fluid-fluid level or pulsation artifact on MR images. Enhancement following intravenous administration of gadolinium contrast material is highly variable, ranging from nonenhancing to ringlike to intense homogeneity. Leptomeningeal spread of a ganglioglioma is rare. Gangliogliomas produce heterogeneous metabolic activity on PET images.
Gangliogliomas contain both ganglion and glial elements of varying differentiation. Gangliogliomas and gangliocytomas are part of the family of tumors composed of mature ganglion cells and dysplastic neurons. Corresponding immunoreactivity for these two cellular populations is noted with appropriate immunohistochemical stains, typically glial fibrillary acidic protein for the glial cells and synaptophysin and neurofilament protein for the neuronal group. The glial component is absent in gangliocytomas. Only gangliogliomas contain neoplastic glial cells, typically composed of astrocytes in varying states of differentiation. These glial cells directly affect the biologic behavior of the tumor. Since most gangliogliomas have astrocytes with histologic features more typical of a low-grade pilocytic astrocytoma, the biologic behavior of these lesions tends to be benign and correlates with the slow growth typically seen in these lesions. In the rare instance of a biologically aggressive ganglioglioma, the astrocytic cells are less differentiated and more similar to those seen in higher-grade glial neoplasms .Despite the presence of aggressive histologic features, the biologic behavior of these anaplastic gangliogliomas is quite variable. Some patients with these tumors will die secondary to diffuse dissemination of their disease, whereas others may have extended survival times following surgical intervention. The location of the tumor appears to have the most effect on the eventual
Gross total resection of gangliogliomas is recommended as the treatment of choice, resulting in resolution of seizure activity for the majority of patients. The role of radiation therapy and chemotherapy has been debated in the literature. Most authorities believe that radiation therapy and chemotherapy should be reserved for those patients with rare malignant forms of ganglioglioma (eg, anaplastic ganglioglioma), disease progression, or an unresectable ganglioglioma (eg, one located in the optic nerve, optic chiasm, or hypothalamus). The deleterious side effects on the developing nervous system of children with these tumors are cited as a strong argument against the use of radiation as a primary therapeutic modality
| References: |
2. Gangliogliomas: A Report of Five Cases. By: Nair, V.; Suri, V.S.; Tatke, M.; Saran, R.K.; Malhotra, V.; Singh, D.. Indian Journal of Cancer, Jan-Mar2004, Vol. 41 Issue 1, p41-46.3. DESMOPLASTIC INFANTILE GANGLIOGLIOMA. By: Izban, Keith F.; Thomas, Chinnamma. Pediatric Pathology & Molecular Medicine, Mar1998, Vol. 18 Issue 2, p157-172, 16p4. Desmoplastic cerebral glioblastoma of infancy. By: Al-Sarraj, S. T.; Bridges, L. R.. British Journal of Neurosurgery, Apr96, Vol. 10 Issue 2, p215-219, 5p, 9bw
Desmoplastic infantile ganglioglioma - A case report. By: Balasubramanian, D.; Ramesh, V.G.; Deiveegan, K.; Ghosh, Mitra; Mallikarjuna, V.S.; Annapoorneswari, T.P.; Chidambaranathan, N.; Ramani, K.V.N.. Neurology
| Comments: |
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| Additional Details:|
Case Number: 647376Last Updated: 08-20-2006 The reader is fully responsible for confirming the accuracy of this content.
The reader is fully responsible for confirming the accuracy of this content.