Gliomatosis cerebri: a brain tumour which is too difficult to treat?

Patterns of presentation and failure in patients with gliomatosis cerebri treated with partial-brain radiation therapy

BACKGROUND

The patterns of lobar involvement, optimal treatment, and disease course among patients with gliomatosis cerebri (GC) have not been fully characterized. The current study evaluates the clinical presentations and outcomes for patients with GC treated with radiation therapy (RT) at our institution.

METHODS

A total of 26 patients (25 with follow-up) with GC were diagnosed and treated between January 2004 and June 2012. Inclusion criteria consisted of brain magnetic resonance imaging and neuroradiology confirmation of contiguous involvement of ≥ 3 lobes/lobar equivalents with preservation of neural architecture. Patients were treated with either partial-brain RT to involved tumor (25 patients) or whole-brain RT (1 patient). The median RT dose was 54.0 Gray. The median follow-up was 17.3 months.

RESULTS

The median age of the patients at the time of diagnosis was 57 years. Twenty-one patients (81%) and 5 patients (19%) had 3 to 6 and ≥ 7 involved lobes/lobar equivalents, respectively. The median progression-free survival and overall survival were 7.4 months and 14.9 months, respectively. Fifteen patients experienced radiographic disease progression after partial-brain RT, 14 of whom (93%) developed infield disease recurrence. On univariate analysis, higher tumor grade and type II GC (with focal mass) were associated with a poorer progression-free survival. The extent of lobar involvement and chemotherapy were not associated with overall survival.

CONCLUSIONS

Even with partial-brain RT, nearly all disease recurrences were infield and clinical outcomes were similar to previous GC series, thereby suggesting that whole-brain RT is not necessary for this patient population. A greater number of involved lobes did not correlate with inferior outcomes. Further studies are necessary to establish more uniform and optimal treatments for this rare disease.

Presentation patterns and outcome of gliomatosis cerebri

A total of 25 patients with gliomatosis cerebri (19 males and 6 females; median age 51 years, range 10-73 years) were diagnosed and treated at the Sheba Medical Center between 1995 and 2009. Of these, 3 patients were 10 years old at the time of diagnosis. Seizures were the initial clinical presentation in 19 patients, focal signs in 16 patients, headaches in 7 patients, cognitive disorder in 4 patients and rapidly progressive hemiparesis in 1 patient. Magnetic resonance imaging (MRI) was performed in the patients and demonstrated a diffuse infiltrative process with a hyperintensity signal on T2-weighted images and a minimal mass effect. Some level of enhancement on MRI was observed in 6 patients. The infiltrative process involved at least two lobes in each patient. Biopsy was performed for diagnosis in the majority of patients. In 1 patient with a markedly rapid deterioration, the diagnosis was established at autopsy. The pathology was compatible with gliomatosis with a diffuse infiltrative low-grade astrocytoma in 21 patients and anaplastic astrocytoma in 5 patients. The patients were treated with whole-brain radiation therapy and 7 patients were treated with combined whole-brain radiation therapy and chemotherapy. Treatment appeared to stabilize 6 patients or improve the clinical condition in 7 patients. Due to the small number of patients in the present study, however, further studies are required to determine the effect of treatment on the natural history of the disease.

Impact of adjuvant chemotherapy for gliomatosis cerebri

Background

Gliomatosis cerebri (GC) is characterized by a diffuse infiltration of tumor cells throughout CNS, however, few details are available about the chemotherapeutic effect on GC. The aim of this study was to investigate its clinical course and to determine the efficacy of chemotherapy for GC.

Methods

Between Jan. 1999 and Dec. 2004, 37 GC patients were diagnosed by biopsy and treated with radiotherapy in a single institution. To determine the efficacy of chemotherapy for GC, we retrospectively reviewed their clinical courses. The study cohort was divided into 2 groups, those with and without receiving post-radiotherapy adjuvant chemotherapy such as temozolomide or nitrosourea-based chemotherapy.

Results

Nineteen patients with adjuvant chemotherapy were assigned to the chemotreatment group and 18 with radiotherapy alone were assigned to the control group. Mean survival for chemotreatment group and control group were 24.2 and 13.1 months, respectively (p = 0.045). Time to progression for these groups were 16.0 and 6.0 months, respectively (p = 0.007). Overall review of the clinical course of patients with GC provided that early appearance of new contrast-enhancing lesions within 6 months from the initial diagnosis and higher histological grade were closely associated with poor survival (p < 0.001 and p = 0.008).

Conclusion

Adjuvant chemotherapy following radiotherapy could prolong the survival in patients with GC. In addition, newly developed contrast-enhanced lesions on the follow-up MR images indicate the progression of GC.

Value of diagnosis and differential diagnosis of MRI and MR spectroscopy in gliomatosis cerebri

PURPOSE

The purpose of this study was to characterize gliomatosis cerebri on magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS), and to analyze the value of these two techniques in diagnosis and differential diagnosis of gliomatosis cerebri.

MATERIALS AND METHODS

MR images of 14 patients with gliomatosis cerebri were reviewed retrospectively; seven of the patients also underwent MRS (single-voxel point-resolved spectroscopy, and chemical-shift imaging point-resolved spectroscopy). Tumorous were confirmed by surgery and biopsy. The distribution, extension and signal features of lesions were assessed, and the MR spectroscopy results were analyzed.

RESULTS

Tumors involved at least two lobes of the brain in all patients. Widespread invasion with isointensity or hypointensity on T1-weighted MR images and hyperintensity on T2-weighted images were found while no prominent necrosis, hemorrhage or contrast enhancement was found. All patients who underwent MRS showed elevated Cho/Cr and Cho/NAA levels as well as decreased NAA/Cr ratios in the abnormal areas on T2-weighted images, three of which showed a lactate doublet. Anaplastic lesions had higher Cho/NAA levels in three cases. Abnormality of metabolism was also seen in the margin of the lesion that was normal on T2-weighted images.

CONCLUSION

MRI and MRS are valuable techniques for diagnosis and differential diagnosis of gliomatosis cerebri. Combining clinical information and MRI findings, as well as MRS, is crucial for making a definitive diagnosis.

Gliomatosis cerebri: quantitative proof of vessel recruitment by cooptation instead of angiogenesis

Object. Gliomas are the most common primary brain tumors, many of which (especially astrocytic and oligodendroglial neoplasms) are characterized by diffuse infiltrative growth in the preexisting brain tissue. Gliomatosis cerebri is a rare glial tumor and represents an extreme example of such diffuse infiltrative growth. This growth pattern not only hampers curative treatment but also allows for vessel cooptation rather than tumor angiogenesis as a way of vessel recruitment by the tumor tissue. The goal of this study was to establish the extent to which tumor angiogenesis occurs in gliomatosis cerebri.

Methods. Computerized image analysis was performed to assess quantitatively two microvascular parameters (vessel density and diameter) in different areas of a brain harboring a gliomatosis cerebri. These regions were the cerebral white and gray matter in which there was a diffuse infiltrative tumor, cerebral white and gray matter in which there was a more compact growth pattern of tumor cells, and normal cerebral white and gray matter. In addition, the authors performed immunohistochemical stainings for blood—brain barrier (BBB) characteristics (Glut-1 and PgP) on samples obtained in these different areas.

The results of the quantitative analysis strongly indicated that in gliomatosis cerebri tumor, angiogenesis was completely absent, a finding that is corroborated by the fact that the microvasculature in gliomatosis cerebri persists in exhibiting immunohistochemical characteristics of the BBB.

Conclusions. The results of this study may help resolve the difficulties in radiological detection and delineation of the diffuse infiltrative part of glial brain tumors and put the expectations for antiangiogenic treatment of such tumors into perspective.

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.