Oligodendroglial gliomatosis cerebri: (1)H-MRS suggests elevated glycine/inositol levels

Fluctuation of Clinical Signs With Near-Syncopal Episodes in a Dog With Gliomatosis Cerebri: A Diagnostic Challenge

A 2-year-old Bull Mastiff cross Boxer neutered male dog was evaluated because of 2-month history of non-progressive right head tilt and mild vestibular ataxia. MRI of the brain revealed a faint T2W, FLAIR, DWI and ADC heterogenous hyperintense and T1W isointense intra-axial lesion with indistinct margins at the level of the pons and medulla oblongata. The lesion did not show any susceptibility artefact on T2* GRE images or contrast enhancement and CSF analysis was normal. Analysis of the spectra from MRS of the thalamus not promptly available at the time of the MRI study revealed a decreased level of NAA, as seen in people with gliomatosis cerebri. The dog represented 3 weeks later and, on this occasion, displayed left-sided head tilt, left-sided postural reaction deficits and near-syncopal episodes associated with state of confusion. Repeated MRI revealed a larger non-enhancing intra-axial lesion with a more hyperintense signal than previously described. CSF was normal and PCR of CSF for infectious diseases was negative. Thoracic and abdominal computed tomography did not reveal any primary or metastatic process. Immunosuppressive treatment was attempted and the dog remained stable over 5 days, then developed generalized tonic-clonic seizures which led to status epilepticus and death. Histopathology supported the diagnosis of gliomatosis cerebri. Gliomatosis cerebri remains difficult to diagnose ante-mortem, due to the broad age of onset and the variable duration and wide range of clinical signs. The mismatch between MRI findings and clinical presentation, the fluctuating clinical signs with near-syncopal episodes associated with a state of confusion, the presence of an infiltrative brain disease as depicted on MR imaging and a normal CSF analysis, should prompt the clinician to consider possible diagnosis of a widespread infiltrative neoplasm. Although, MRS may help narrow the differential diagnosis in favor of a neoplastic lesion, the overall prognosis remains poor.

Detection of nonketotic hyperglycinemia in a neonate using proton magnetic resonance spectroscopy

Nonketotic hyperglycinemia (NKH) is a rare metabolic disorder caused by a defect in the glycine cleavage enzyme system, resulting in high glycine concentrations in the brain. We report a neonate in which proton magnetic resonance spectroscopy provided biochemical evidence of elevated brain glycine levels and facilitated early diagnosis of NKH and guided clinical management.

An uncommon cause of transient neurological dysfunction

Transient neurological dysfunction may be associated with uncommon disorders and should prompt consideration of a broad differential diagnosis when assessing patients with episodic symptoms. The most common causes of transient neurological dysfunction include transient ischemic attack (TIA), seizure disorder, and migraine and its variants. However, underlying unusual pathophysiological processes such as brain tumors can also cause transient neurological dysfunction. Here we present a case of a 68-year-old male with oligodendroglial gliomatosis cerebri (OGC) who presented with TIA-like symptoms. Brain magnetic resonance imaging revealed multiple diffuse T2 hyperintensities within the white and gray matter. Magnetic resonance spectroscopy was suggestive of gliomatosis cerebri and was particularly helpful in this case. The diagnosis of OGC was confirmed by histopathology and molecular genetic studies on brain biopsy tissue. In this report, we discuss the clinical and radiological characteristics of OGC and highlight the unusual presentation of this case.

Gliomatosis cerebri: clinical characteristics, management, and outcomes

Gliomatosis cerebri is a rare diffusely infiltrating primary neoplastic glial process of the brain. Our objective is to review clinical presentation, management, and outcome in a large single institution series of gliomatosis cerebri patients. 54 consecutive gliomatosis cerebri cases presenting to Mayo Clinic Rochester between 1991 and 2008 were retrospectively reviewed. Inclusion criteria included involvement of at least three cerebral lobes, lack of a single discrete mass and pathological confirmation of diffuse glioma. Median overall survival (OS) was 18.5 months. Age, gender, presenting symptoms, and contrast enhancement did not correlate significantly with survival, though there was a trend toward decreased overall survival in patients above the median age of 46 years. Karnofsky performance score <70 was associated with poor OS (median 9.5 vs. 20.5 months, p = 0.02). Higher histologic grade was associated with poor progression-free survival (PFS; median for WHO grades II, III, and IV: 21.5, 6.5, and 4 months; p = 0.03) and OS (median 34, 15.5, and 8.5 months; p < 0.05). Radiation therapy was strongly associated with better prognosis (PFS 16.5 vs. 4.5 months, p < 0.01; OS 27.5 vs. 6.5, p < 0.01), but chemotherapy was not. Gliomatosis cerebri patients have a poor prognosis. Lower KPS upon presentation and higher histologic grade predict decreased survival. Surgery's role is limited beyond biopsy for diagnostic purposes. Radiotherapy appears beneficial, although selection bias could be present in this retrospective study. Chemotherapy's value is not as clear but this must be interpreted with caution given variable treatment regimens in this series.

Gliomatosis Cerebri in Two Dogs

A 3.5 yr old Saint Bernard was evaluated for nonambulatory tetraparesis and cranial nerve dysfunction, and a 7 yr old rottweiler was evaluated for progressive paraparesis. Clinical signs of left-sided vestibular and general proprioceptive ataxia and cranial nerve VII dysfunction in the Saint Bernard suggested a lesion affecting the brain stem. Signs in the rottweiler consisted of general proprioceptive/upper motor neuron paraparesis, suggesting a lesion involving the third thoracic (T3) to third lumbar (L3) spinal cord segments. MRI was normal in the Saint Bernard, but an intra-axial lesion involving the T13–L2 spinal cord segments was observed in the rottweiler. In both dogs, the central nervous system (CNS) contained neoplastic cells with features consistent with gliomatosis cerebri (GC). In the Saint Bernard, neoplastic cells were present in the medulla oblongata and cranial cervical spinal cord. In the rottweiler, neoplastic cells were only present in the spinal cord. Immunohistochemistry disclosed two distinct patterns of CD18, nestin, and vimentin staining. GC is a rarely reported tumor of the CNS. Although GC typically involves the cerebrum, clinical signs in these two dogs reflected caudal brainstem and spinal cord involvement.

Gliomatosis cerebri in a patient with Ollier disease

Gliomatosis cerebri (GC) is an uncommon brain tumour defined as a diffuse neoplastic glial cell infiltration of the brain, involving more than two cerebral lobes and, occasionally, the infratentorial structures or the spinal cord. GC of the oligodendroglial phenotype is extremely rare, especially in the paediatric setting. We describe an unusual case of oligodendroglial GC diagnosed in a 16-year-old boy with Ollier disease. To our knowledge this is the first case of GC reported in a child with Ollier disease.

Combined surgery, radiation, and chemotherapy for oligodendroglial gliomatosis cerebri

Gliomatosis cerebri (GC), which mainly consists of oligodendroglial tumour cells, is rare and six cases have been documented to date. We present a new case of oligodendroglial gliomatosis cerebri with a favourable response to combination treatment using surgery, radiotherapy and chemotherapy.

1H MR spectroscopic imaging with short and long echo time to discriminate glycine in glial tumours

OBJECT

To investigate glycine (Gly) concentrations in low- and high-grade gliomas based on (1)H MR spectroscopic imaging (MRSI) with short and long echo time (TE). Myoinositol (MI) and Gly appear at the same resonance frequency of 3.56 ppm, but due to strong coupling the MI signal dephases more rapidly. Therefore, their contribution to the 3.56 ppm signal should be distinguishable comparing MRSI data acquired at short and long TE.

MATERIALS AND METHODS

(1)H MRSI (TE = 30 and 144 ms) was performed at 3 T in 29 patients with histopathological confirmed World Health Organization (WHO) grade II-IV gliomas and in FIVE healthy subjects. All spectra from the gliomas revealed increase of the 3.56 ppm resonance in the short TE spectra. Signal intensities of Gly and MI were differentiated either by analysing the short to long TE ratio of the resonance or by performing a weighted difference. Gly concentrations were compared between high-grade (WHO III-IV) and low-grade gliomas.

RESULTS

High-grade gliomas showed significantly higher Gly concentrations compared to low-grade gliomas.

CONCLUSION

Appropriate data processing of short and long TE (1)H MRSI provides a tool to distinguish and to quantify Gly and MI concentrations in gliomas. As Gly seems to be a marker of malignancy, more dedicated spectroscopic methods to differentiate these metabolites are justified.

Spectroscopic metabolomic abnormalities in the thalamus related to auditory hallucinations in patients with schizophrenia

OBJECTIVE

Previous studies have found neurochemical abnormalities in thalamic nuclei in patients with schizophrenia. These abnormalities have been associated with information processing deficiencies and symptom formation. There are no metabolic spectroscopy studies in patients with schizophrenia attending to auditory hallucinations. The aim of the present study is to explore metabolic Magnetic Resonance Spectroscopy (MRS) ratio differences in the thalamus between schizophrenic patients with and without auditory hallucinations and control subjects.

METHODS

MRS studies (MRI 1.5 T unit) were performed in 49 patients with schizophrenia (30 with auditory hallucinations and 19 without auditory hallucinations) and 37 controls. (1)H MRS imaging was used to acquire 2 transverse slices (TR/TE 2700/272 ms, region of interest 110 x 100 x 23 mm). In the quantitative analysis four elements of volume (9.2 x 9.2 x 23 x 4 mm), added into one spectrum representative of each thalamus, were chosen in the slice passing through the main body of the thalamus. The areas of metabolites were integrated with the jMRUI program.

RESULTS

The patients with schizophrenia had significantly lower bilateral NAA/Cho ratios when compared with healthy subjects. There was also a lower NAA/Cho ratio in the right thalamus in patients with auditory hallucinations compared to patients without auditory hallucinations and control subjects. Significant correlations were found between metabolic ratios and BPRS, PANSS and PSYRATS scores, age of onset of auditory hallucinations, and age of subjects.

CONCLUSIONS

Choline and NAA ratio abnormalities determined by thalamic spectroscopy may be related to the pathogenesis of auditory hallucinations in patients with schizophrenia.

Myo-inositol: a marker of reactive astrogliosis in glial tumors?

In a prospective study, two-dimensional (1)H-MRS with TE of 30 ms was performed before surgery in 56 patients with glial brain tumors. Concentrations of myo-inositol (MI), trimethylamine (TMA) and creatine/phosphocreatine (tCr) were evaluated for the whole tumor and scaled to the normal-appearing contralateral brain tissue. To assign changes in MI to specific tissue pathology, the normalized peak and mean concentrations of MI were correlated with TMA and tCr concentrations. TMA is accepted as a marker of proliferating tumor tissue, and tCr might be a marker of reactive astrogliosis. The mean and peak concentrations of MI and tCr correlated positively (r = 0.7), but not the concentrations of MI and TMA. The absolute concentration of MI was significantly increased in all tumor tissues (5.55 +/- 2.92 mM; mean +/- SD) compared with the normal-appearing white matter (4.33 +/- 1.22 mM, p = 0.005), with the highest concentrations for gliomatoses (n = 10) and grade II oligoastrocytomas (n = 3). Significant differences (P = 0.004) between low- and high-grade astrocytomas were found for TMA (1.67 +/- 0.32 mM and 2.65 +/- 0.86 mM, respectively), but not for MI (5.92 +/- 1.98 mM and 5.49 +/- 3.27 mM, respectively). As increased MI and tCr concentrations were found in gliomatosis and other cerebral diseases associated with marked astrogliosis, this process may also be responsible for the observed changes in MI in other glial tumors.

Gliomatosis cerebri--an uncommon neuroepithelial tumor in children with oligodendroglial phenotype

Gliomatosis cerebri(GC) is a highly aggressive, rare form of neuroepithelial tumor. Due to the diffuse nature of the tumor, its pathological grade is not conclusively established unless a biopsy is carried out from multiple sites. The tumor typically infiltrates the cortex in the subpial plane and also insinuates in the perineuronal space and around the Virchow-Robin spaces with relative preservation of the underlying brain parenchyma. Most of the previously reported cases of GC are astrocytic in nature. In this study, we report 2 pediatric patients of GC with oligodendroglial morphology on histopathological examination. In view of the rarity of the oligodendroglial phenotype of gliomatosis cerebri as well as the rare occurrence in children, we report these 2 cases.

Automated MR spectroscopy of intra- and extraventricular neurocytomas

PURPOSE

We evaluated the automated magnetic resonance spectroscopic (MRS) characteristics of intra- and extraventricular neurocytomas.

MATERIALS AND METHODS

One extra- and 4 intraventricular neurocytomas were studied. Automated single-voxel proton MRS was performed with a 1.5 T MR scanner. The results of 6 total automated MR spectra were analyzed for each tumor.

RESULTS

Lactate resonance was detected as a doublet in 3 MR spectra of 2 intraventricular neurocytomas. A peak corresponding to N-acetylaspartate (NAA) was small in 5 MR spectra of 4 intraventricular neurocytomas. Creatine (Cr) resonance was detected in all 6 MR spectra. Prominent choline (Cho) resonance was found in all 6 MR spectra. The myoinositol (MI) and/or glycine (Gly) peaks were large in 3 MR spectra of 2 intraventricular neurocytomas.

CONCLUSION

The presence of the NAA signal and high MI and/or Gly signals may be characteristic features of intraventricular neurocytomas. A combination of prominent Cho resonance and detectable Cr resonance is a common feature of both intra- and extraventricular neurocytomas.

Lactate, choline, and creatine levels measured by vitro 1H-MRS as prognostic parameters in patients with non-small-cell lung cancer

PURPOSE

To determine the biochemical characteristics of lung cancer tissue using in vitro (1)H-MRS, and investigate the correlation between survival probabilities and lactate (Lac), creatine (Cr), and choline (Cho) concentrations measured by in vitro (1)H-MRS.

MATERIALS AND METHODS

A total of 21 patients with lung cancer were included in this retrospective study. (1)H-MRS spectra measurements were performed at 6.35T using a JNM-EX270, high-resolution FT-NMR spectrometer.

RESULTS

When normal lung tissue was compared with lung cancer tissue, significant differences were noted most consistently in the levels of Lac and Cho, with lung cancer tissue showing higher values than normal lung tissue. Lac concentrations of lung cancer tissue were significantly higher in patients with recurrence compared to patients without recurrence (0.285 +/- 0.096 mumol/g). The mean overall survival of patients in the low-Lac group was 50.28 +/- 6.47 months, which is significantly higher compared to the high-Lac group, which had a mean survival time of only 30.49 +/- 5.41 months.

CONCLUSION

Kaplan-Meier analysis of the data showed that the overall and disease-free survival probabilities were significantly higher in patients with low tumor Lac values than in those with high tumor Lac concentrations.

1H MR spectroscopy in the assessment of gliomatosis cerebri

OBJECTIVE

Gliomatosis cerebri is a rare brain tumor with a short survival time; for this reason, it is difficult to establish the degree of aggressivity in vivo. The MR spectroscopic findings on this tumor often do not agree with choline level. The purpose of this study was to evaluate whether MR spectroscopy can be used to measure tumor choline levels and whether the findings give useful information about tumor growth rate and patient survival time.

SUBJECTS AND METHODS

We performed MRI and 1H MR spectroscopic studies on seven treatment-naive patients with gliomatosis cerebri and on 16 healthy volunteers. We then analyzed the association between survival time and levels of choline (Cho) and N-acetyl aspartate (NAA) normalized to creatine (Cr).

RESULTS

The results showed a statistically significant (p = 0.05) inverse relation between Cho/Cr ratio and survival time. In addition, NAA/Cr ratio was significantly lower in the patient group than in the control group (p = 0.001).

CONCLUSION

Cho/Cr ratio measured with MR spectroscopy seems to be related to survival time, possibly explaining the inconsistent findings previously reported for this parameter.

Molecular genetic alterations in gliomatosis cerebri: what can we learn about the origin and course of the disease?

Gliomatosis cerebri (GC) is a neuroepithelial neoplasm with extensive infiltration of large parts of the brain. Recent data showing the involvement of TP53 mutation or nuclear protein accumulation in some cases have linked the astrocytic phenotype of the tumor cells to TP53 alterations frequently found in common astrocytomas. However, the frequency of these alterations is low, and other molecular genetic changes have been only rarely identified. Those found in common high-grade astrocytomas and glioblastomas are usually missing in GC. The distribution of TP53 point mutations, as well as non-coding polymorphic markers and some cytogenetic data, support a monoclonal origin in some cases, and are at least compatible with it in most cases, while no conclusive data suggesting a polyclonal origin have been reported. This raises the question of mechanisms responsible for the enhanced infiltrative potential of the tumor cells in this disease, which have not yet been identified.

Gliomatosis cerebri: a review of 22 cases

OBJECTIVE

Gliomatosis cerebri is an enigmatic diffuse brain neoplasm whose prognosis is grim. We reviewed data for patients with gliomatosis who were treated at the University of California, San Francisco, during a 10-year period. Our focus was on presentation, radiological and pathological features, and outcomes.

METHODS

We reviewed hospital and clinic records and magnetic resonance imaging scans for 22 patients with gliomatosis. The diagnosis was based on magnetic resonance imaging findings and tissue confirmation for all patients. Seven patients also underwent magnetic resonance spectroscopy. Eleven patients were male (50%), and the median age at presentation was 49 years (range, 7-79 yr).

RESULTS

Kaplan-Meier analysis demonstrated median lengths of survival as follows: no treatment, 1 month (n = 4); radiotherapy alone, 28 months (95% confidence interval, 5-51 mo; n = 13); radiotherapy followed by chemotherapy, two patients, alive at 28 and 104 months; radiotherapy and chemotherapy simultaneously, three patients, one alive at 18 months and the others dead at 7 and 9 months. There was no significant difference between radiotherapy alone and radiotherapy combined with chemotherapy (P = 0.69). Karnofsky Performance Scale scores of >/=70 and grade were both significantly related to length of survival in univariate analyses (P < 0.05); these correlations were confirmed in the multivariate analysis, although the small numbers of patients and deaths precluded reliable interpretation.

CONCLUSION

Although the small number of patients in our study and its retrospective nature preclude definitive conclusions regarding the utility of treatment, our findings suggest that biopsies are useful not only for diagnosis but also for prediction of the length of survival.

The glycine peak in brain diseases

Glycine is an excitatory amino acid, a neurotransmitter for the brain. A recent experimental study by a 9.3T laboratory spectrometer identified the peak of pure glycine at 3.52 ppm, and in a clinical case this peak was demonstrated at 3.50 ppm by a 1.5 T clinical scanner. This study was undertaken to investigate the brain diseases having the glycine peak. An experiment with a 1.5 T clinical MRI unit was performed. Two grams of pure glycine was dissolved in 200 cc of distilled water and the solution was frozen, and proton MR spectroscopy (TR=1500 ms, TE=20 ms) was obtained. Nine patients with various diseases studied by two-dimensional chemical shift spectroscopy (hybrid CSI) with TR=1500 ms, and TE=40 ms are included in the study. Ten normal cases were available for comparison. In the experiment with the clinical MRI unit, the glycine peak was centered at 3.50 ppm. The disease processes associated with distinct glycine peaks at 3.50 ppm included infarction, high-grade astrocytoma, megalencephalic leukoencephalopathy with cysts, Leigh's disease, adrenoleukodystrophy, congenital muscular dystrophy, Rasmussen's encephalitis, gliosis in neuronal migrational disorder, and hamartoma in tuberous sclerosis. None of the control cases displayed a glycine peak. In conclusion, glycine has a peak centered at 3.50 ppm in in vivo environments. It is distinct from the myoinositol peak. Detection of glycine in a wide variety of brain diseases ranging from infarction, tumor, leukoencephalopathies, infection to gliosis likely reflects presence of excitotoxic brain damage or a disturbance of neurotransmitting mechanisms in these conditions.

False localising signs

Neurological signs have been described as "false localising" if they reflect dysfunction distant or remote from the expected anatomical locus of pathology, hence challenging the traditional clinicoanatomical correlation paradigm on which neurological examination is based. False localising signs occur in two major contexts: as a consequence of raised intracranial pressure, and with spinal cord lesions. Cranial nerve palsies (especially sixth nerve palsy), hemiparesis, sensory features (such as truncal sensory levels), and muscle atrophy, may all occur as false localising signs. Awareness that signs may be false localising has implications for diagnostic investigation.

Use of proton magnetic resonance spectroscopy of the brain to differentiate gliomatosis cerebri from low-grade glioma

OBJECT

Gliomatosis cerebri (GC), a rare entity characterized by a widespread infiltration of brain by tumor, lacks objective and quantitative diagnostic criteria. Single-voxel spectroscopy and chemical shift imaging (two-dimensional proton magnetic resonance [MR] spectroscopy) were performed using both short (20- or 22-msec) and long (135-msec) echo times in nine patients suffering from GC, nine patients with low-grade gliomas (LGGs), and 25 healthy volunteers to establish the precise metabolic pattern of this uncommon brain neoplasm.

METHODS

The gliomatosis infiltration was characterized by markedly elevated levels of creatine-phosphocreatine (Cr) and mvo-inositol (Ins), a reduced level of N-acetyl aspartate (NAA), and a moderately elevated level of choline-containing compounds (Cho). This pattern differs strikingly from LGGs, which are characterized by elevated levels of Cho and Ins, markedly reduced levels of NAA, and low-to-normal Cr concentrations. Although the distinction between GC and LGG, based on histological and MR imaging criteria, is a matter of debate, MR spectroscopy produces valuable information for the differentiation between these two entities and, hence, the choice of therapeutic strategy. It also provides new insight into the pathophysiology of GC because elevated Cr and Ins levels may be related to proliferation of glial elements or, more probably, activation of normal glia. Elevated levels of Cho reflect cellular proliferation and reduced NAA corresponds to reversible neuronal injury and/or focal invasion by the tumor process.

CONCLUSIONS

Owing to the unfavorable clinical outcome associated with GC compared with that associated with LGG, the findings of this study illustrate the diagnostic and prognostic value of proton MR spectroscopy in the characterization of infiltrating gliomas.

Posterior fossa decompression for life-threatening tonsillar herniation in patients with gliomatosis cerebri: report of three cases

OBJECTIVE AND IMPORTANCE

Gliomatosis cerebri (GC) is a rare type of primary brain tumor that diffusely infiltrates more than two lobes of the brain while the normal cerebral architecture is maintained. To the best of our knowledge, the association between an acquired tonsillar herniation and GC has never been reported. In this article, we describe three patients with progressive gliomatosis of the cerebellar hemispheres who subsequently showed signs and symptoms secondary to tonsillar herniation. Early recognition of this potentially life-threatening complication allowed us to recommend prompt surgical intervention.

CLINICAL PRESENTATION

One patient with primary, or Type I, GC presented with suboccipital headaches, and two patients with secondary, or Type II, GC presented with the signs and symptoms of progressive myelopathy. Serial imaging studies demonstrated progressive involvement of the cerebellum, descent of the cerebellar tonsils through the foramen magnum, and cervicomedullary spinal cord compression.

INTERVENTION

Once the tonsillar herniation was recognized, all three patients underwent posterior fossa decompression, a cervical laminectomy to the lowest level of the tonsillar herniation, and duraplasty. All three patients experienced immediate improvement in their conditions.

CONCLUSION

Early recognition of tonsillar herniation, a possibly overlooked cause of death in patients with GC, allows for early surgical intervention as a potentially lifesaving procedure and significant improvement in the patient's condition.

Histological and genetic diagnosis of gliomatosis cerebri: case report

Gliomatosis cerebri is considered grade III astrocytoma because of the short survival period of patients with this tumor, while the tumor histologically consists of widespread low grade astrocytoma cells. The authors tried to clarify this discrepancy by applying genetic analysis of the tumor. A 29-year-old man originally presented with mild headache and showed diffuse high intensity areas in both hemispheres and in the cerebellum by T2-weighted magnetic resonance imaging (MRI) without gadolinium-dimeglumine (Gd)-enhancement in T1-weighted imaging. Histological diagnosis was gliomatosis cerebri with diffuse grade II astrocytoma. Seven months after temporary improvement following irradiation and chemotherapy, he developed progressive mental deterioration, and died in one year after the surgery. At this time T1-weighted imaging showed Gd-enhanced lesions with enlargement only of the cerebellar tumor. Genetic analysis demonstrated positive FGFR 1 and less FGFR 2 mRNA in the tumor tissue, and FGFR 1 mRNA was beta type dominant. These results indicated that the genetic features of this tumor are similar to those of glioblastoma multiforme concerning FGFR expression. The authors conclude that genetic investigation of the tumor tissue is required to predict the prognosis of gliomatosis cerebri patients, in addition to imaging and histological examinations.