Primary sellar neuroblastoma. A new case and review of literature.

The primary intracranial development of olfactory neuroblastomas, outside olfactory epithelium, is rare. We report a case of primary sellar neuroblastoma without any aggressive histopathological features, managed solely surgically without adjuvant therapy, with good outcomes at 3 years. Primary sellar neuroblastomas mostly occur in women in the 4th decade with a context of a non-secreting pituitary tumour. Diagnosis is made on histopathological examination (small cells, fibrillary intercellular background, strong immunoreactivity for neurons markers, negative immunoreactivity for anterior pituitary hormones). Management is based on surgery. Adjuvant treatment is not consensual, largely depends on patient's conditions and aggressive histopathological features.

Glomuvenous Malformations (Familial generalized multiple glomangiomas).

A 15-year-old boy with a diagnosis of generalized multiple glomangiomas was referred for evaluation and treatment of enlarging and increasingly painful lesions on his right ankle. The patient underwent a series of two treatments with long-pulsed KTP 1064 nm laser that resulted in substantial improvement in appearance and decreased pain. Generalized glomuvenous malformations, or multiple glomangiomas, are the less common presentation of proliferation of glomus cells and may have extracutaneous involvement. Whereas surgical management is often employed and definitive for solitary lesions, interventions such as laser therapy, may be beneficial for improvement of functional impairment and cosmesis as was observed in our patient.

[Metabolic imaging for supratentorial oligodendrogliomas]. / Les oligodendrogliomes supra-tentoriels: imagerie métabolique.

Metabolic imaging with positron emission tomography (PET) provides, in neuro-oncology, information complementary to that provided by anatomic imaging obtained with CT-scanner or MRI. Only a few publications have yet reported its use in oligodendroglial tumors. These findings and partial results obtained in ongoing work, suggest some preliminary conclusions: 11C-MET (L-methyl-methionine) is a more appropriate tracer than 18F-FDG (fluoro-deoxy-glucose), in terms of both specificity and sensitivity, for the assessment of patients with this category of tumor. PET/MET allows differentiation between grade II and grade III oligodendrogliomas; better targeting for stereotactic biopsy; more accurate assessment of the post-operative residual tumor; identification of progression from low-grade to anaplastic grade during the disease course; differentiation between recurrence and a post-radiation processes. PET/MET allows, to some extent, prediction of response to radiotherapy; and, probably, to chemotherapy.

[Pediatric supratentorial oligodendrogliomas: Marseilles and Lyons experiences]. / Les oligodendrogliomes supratentoriels de l'enfant. A propos des séries arseillaises et lyonnaises.

BACKGROUND AND PURPOSE: The goal of this study was to analyze the main aspects of oligodendrogliomas observed in children. METHOD: The records of 35 children aged 15 years or younger (23 from Marseilles and 12 from Lyons) were reviewed. Clinical signs and symptoms, imaging findings (CT scan and pre- and post-operative MRI), extent of surgical resection, histology according to the WHO and Ste-Anne grading and survival were analysed. Considering all these factors, a statistical analyzis was undertaken in order to identify prognostic factors. DISCUSSION AND CONCLUSION: Oligodendrogliomas are rare tumors in children. The most important differential diagnosis to discuss is dysembryoplastic neuroepithelial tumor. Our study allowed us to distinguish several subgroups of patients with a different prognosis: thalamic tumors with a dismal prognosis versus hemispheric tumors. A group of cortical tumors we called "DNT-like" (hemispheric cortical tumor, isolated epilepsy, without neurological deficit and reased ICP, without edema and mass effect on MRI) with an excellent prognosis like the group with epilepsy. Histological grading (grade A/grade B and grade II/grade III) is also a prognostic factor.

Cerebral gliomas: prospective comparison of multivoxel 2D chemical-shift imaging proton MR spectroscopy, echoplanar perfusion and diffusion-weighted MRI.

Developments in MRI have made it possible to use diffusion-weighted MRI, perfusion MRI and proton MR spectroscopy (MRS) to study lesions in the brain. We evaluated whether these techniques provide useful, complementary information for grading gliomas, in comparison with conventional MRI. We studied 17 patients with histologically verified gliomas, adding multivoxel proton MRS, echoplanar diffusion and perfusion MRI the a routine MRI examination. The maximum relative cerebral blood volume (CBV), minimum apparent diffusion coefficient (ADC) and metabolic peak area ratios in proton MRS were calculated in solid parts of tumours on the same slice from each imaging data set. The mean minimum ADC of the 13 high-grade gliomas (0.92+/-0.27 x 10(-3) mm(2)/s) was lower than that of the four low-grade gliomas (1.28+/-0.15 x 10(-3) mm(2)/s) ( P<0.05). Means of maximum choline (Cho)/N-acetylaspartate (NAA), Cho/creatine (Cr), Cho/Cr in normal brain (Cr-n) and minimum NAA/Cr ratios were 5.90+/-2.62, 4.73+/-2.22, 2.66+/-0.68 and 0.40+/-0.06, respectively, in the high-grade gliomas, and 1.65+/-1.37, 1.84+/-1.20, 1.61+/-1.29 and 1.65+/-1.61, respectively, in the low-grade gliomas. Significant differences were found on spectroscopy between the high- and low-grade gliomas ( P<0.05). Mean maximum relative CBV in the high-grade gliomas (6.10+/-3.98) was higher than in the low-grade gliomas (1.74+/-0.57) ( P<0.05). Echoplanar diffusion, perfusion MRI and multivoxel proton MRS can offer diagnostic information, not available with conventional MRI, in the assessment of glioma grade.

Discrimination of brain abscess and cystic tumor by in vivo proton magnetic resonance spectroscopy.

Proton magnetic resonance (MR) spectroscopy was evaluated for the differentiation of brain abscesses and cystic brain tumors. Proton MR spectroscopy was performed in vivo in two patients with brain abscess and eight patients with various cystic brain tumors (anaplastic astrocytoma, glioblastoma, and metastatic brain tumor). MR imaging with contrast medium demonstrated ring-like enhanced mass lesions in all patients. The various resonance peaks in proton MR spectra were assigned to metabolites according to chemical shifts. Treatment of the cystic brain lesions was based on the information from proton MR spectroscopy. Aspirated pus from one patient with brain abscess was examined using ex vivo proton MR spectroscopy. The in vivo spectra of brain abscess contained resonance peaks attributed to acetate, lactate, alanine, amino acids, and lipids in both cases, and an additional peak of succinate in one case. In vivo spectra of the neoplasms contained resonance peaks corresponding to lactate, lipids, choline, creatine, and N-acetyl aspartate. Proton MR spectroscopy is useful for discriminating brain abscess from cystic tumors with similar neuroimaging appearance, which is very important for determining the treatment strategy.

Radiologic features of pediatric thalamic and hypothalamic tumors.

A variety of histologic subtypes of tumor may affect the thalamus and the hypothalamus in the pediatric population. These tumors have radiologic features that are useful in predicting pathology. We discuss the radiologic findings of childhood thalamic and hypothalamic tumors and provide imaging examples.

Chiasmatic low-grade glioma presenting with sacral intradural spinal metastasis.

Leptomeningeal metastasis of low-grade gliomas in children has been documented in several series, both at the time of diagnosis and at relapse. The authors report a unique case of chiasmatic low-grade astrocytoma presenting with signs and symptoms related to the metastatic site rather than the primary site. In this respect, the possibility of appearance of symptoms and signs related to leptomeningeal dissemination preceding the signs and symptoms belonging to the primary site should be considered in this type of benign tumours.

[A case of hemangioblastoma in the thalamus].

Supratentorial hemangioblastoma is encountered very rarely. About 80 cases in all have been reported. The authors present a case of supratentorial hemangioblastoma in the thalamus with gradually enlarging cysts. The patient was a 45-year-old man with complaints of left hemiparesis and headache. Computed tomographic scans of the brain showed a cystic mass with mural nodule in the right thalamus. Left vertebral angiography demonstrated a vascular tumor fed by a thalamogeniculate artery. A right temporo-parietal craniotomy was performed and the tumor was totally resected through the transcortical approach. The histological diagnosis was hemangioblastoma. Post-operative course was good except for a minor complication of the left lower quadrant homonymous hemianopsia and left hemiparesis which had disappeared at the time of discharge.