Subependymoma of the septum pellucidum: characterization by PET

Spinal cord ependymoma: a review of the literature and case series of ten patients

Spinal cord ependymoma (SCE) is a rare tumor that is most commonly low-grade. Complete surgical resection has been established as first-line treatment and can be curative. However, SCEs tend to recur when complete tumor resection is not possible. Evidence supporting the use of adjuvant radiation and chemotherapy is not definitive. We review the most recent literature on SCE covering a comprehensive range of topics spanning the biology, presentation, clinical management, and outcomes. In addition, we present a case series of ten SCE patients with the goal of contributing to existing knowledge of this rare disease.

Imaging in neurooncology

Imaging in patients with brain tumors aims toward the determination of the localization, extend, type, and malignancy of the tumor. Imaging is being used for primary diagnosis, planning of treatment including placement of stereotaxic biopsy, resection, radiation, guided application of experimental therapeutics, and delineation of tumor from functionally important neuronal tissue. After treatment, imaging is being used to quantify the treatment response and the extent of residual tumor. At follow-up, imaging helps to determine tumor progression and to differentiate recurrent tumor growth from treatment-induced tissue changes, such as radiation necrosis. A variety of complementary imaging methods are currently being used to obtain all the information necessary to achieve the above mentioned goals. Computed tomography and magnetic resonance imaging (MRI) reveal mostly anatomical information on the tumor, whereas magnetic resonance spectroscopy and positron emission tomography (PET) give important information on the metabolic state and molecular events within the tumor. Functional MRI and functional PET, in combination with electrophysiological methods like transcranial magnetic stimulation, are being used to delineate functionally important neuronal tissue, which has to be preserved from treatment-induced damage, as well as to gather information on tumor-induced brain plasticity. In addition, optical imaging devices have been implemented in the past few years for the development of new therapeutics, especially in experimental glioma models. In summary, imaging in patients with brain tumors plays a central role in the management of the disease and in the development of improved imaging-guided therapies.

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.