Case Of Anaplastic Astrocytoma Research Articles

PET in stereotactic conditions increases the diagnostic yield of brain biopsy.

We have recently described a technique allowing routine integration of PET scan data in the planning of stereotactic brain biopsy [Levivier et al:, Neurosurgery, 1992; 31:792-797]. We now report our results in a consecutive series of 38 patients that underwent combined FDG-PET and CT-guided stereotactic biopsy between June 1991 and January 1993. Stereotactic procedures were performed according to a standard protocol in which two biopsy trajectories were used whenever possible. This yielded to a total of 78 trajectories. In 31 patients, at least 1 trajectory was defined using an abnormality visualized on PET. The histological diagnosis was obtained in all cases. The diagnostic yield of each trajectory according to the FDG uptake of PET and contrast enhancement on CT showed that most low-grade tumors were found in hypometabolic/hypodense areas, glioblastomas were all diagnosed in areas with increased FDG uptake and contrast enhancement on CT while data for anaplastic astrocytomas were heterogeneously distributed. In the present series, 6 targets defined on CT were nondiagnostic; this never occurred when targets were defined on FDG-PET. In one case of anaplastic astrocytoma, the diagnosis was only made using a target defined on PET in a normal CT area; the second trajectory was made in a contrast-enhanced area on CT and was nondiagnostic. Because only structural images such as CT or MRI are available preoperatively, we analyzed separately the benefit of FDG-PET-guided biopsy in patients who have either an enhanced- or a nonenhanced lesion on CT. CT-enhanced lesions were found in 27 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Endothelial cell marker PAL-E reactivity in brain tumor, developing brain, and brain disease

The endothelial cell marker PAL-E is not reactive to vessels in the normal brain. The present study concerns the PAL-E reactivity in brain tumors in contrast to normal brain and nonneoplastic brain disease. A total of 122 specimens were examined: brain tumors (n = 94), nonneoplastic brain disease (n = 19), normal brain (n = 8), and fetal brain (n = 1). Standard immunohistochemical procedures using a panel of endothelial cell markers were applied to detect vessels reactive to PAL-E. PAL-E reactivity to endothelial cells was found in all cases of glioblastoma multiforme, in 75% of the cases of anaplastic astrocytoma, and in 46% of the cases of astrocytoma. Furthermore, PAL-E reactivity was present in diseases with a developmental etiology, such as primitive tumors and congenital vascular malformations. The developing human brain (6-weeks' gestation age) and special sites of the mature brain, sites without blood-brain barrier, showed a strong reactivity, which indicates a relation with the status of blood-brain barrier development. PAL-E is the only marker out of a panel of endothelial cell markers that shows no reactivity to endothelial cells in the normal brain with an intact blood-brain barrier. In primary and metastatic brain tumors, PAL-E is reactive to endothelial cells, except for 25% of anaplastic astrocytoma and 54% of astrocytoma. PAL-E reactivity in brain tumors most likely is related to angiogenesis and to blood-tumor barrier properties not present in the normal blood-brain barrier.

Gemistocytic astrocytes are essential components of malignant astrocytomas

Malignant astrocytomas are characterised by the presence of a variety of cell types and according to the classification by Giangaspero & Burger, include small anaplastic cells, small fibrillated cells, fibrillated astrocytes, pleomorphic astrocytes, gemistocytic astrocytes, large bizarre cells and more recently, lipidized cells. Most classifications of central nervous system tumours retain gemistocytic astrocytoma as a distinct subgroup of low grade astrocytoma, but concede that, in a pure form, they rarely occur. In fact, there has been scanty information in recent literature concerning gemistocytic astrocytoma. We examined retrospectively 78 cases of glioblastoma multiforme and 33 cases of anaplastic astrocytoma, according to the diagnostic criteria of Burger & Vogel, and searched for geniistocyte-like cells, grading them +, ++, +++ when they were present focally, in small clusters and in sheets respectively. 51 glioblastoma multiforme (65%) and 21 anaplastic astrocytoma (54%) were found to contain gemistocytic foci. Overall, 44 cases (40%) contained ++ or +++ lesions, with areas that resemble a gemistocytic astrocytoma. However, careful examination invariably revealed a close intermingling with or transformation to small anaplastic cells, bizzare cells and lipidized cells and the occurrence of tumour necrosis and hyperplastic vascular elements in adjacent areas. Immunohistochemically, gemistocytes were mostly positive for GFAP and occasionally positive for cytokeratin. We conclude that gemistocytes are a carmon and essential cellular component of malignant astrocytomas. When gemistocytes <i>are</i> encountered in diagnostic neuropathology, deligent search for other histologic criteria for malignancy is warranted. A pure form of low grade gemistocytic astrocytoma is probably a pathologic curiosity.

Stereotactic Biopsy in the Diagnosis of Brain Masses: Comparison of Results of Biopsy and Resected Surgical Specimen

We report the pathological accuracy of image-directed stereotactic brain biopsy in 30 patients who had mass lesions of the brain and subsequently underwent resection of the mass. The histological diagnosis at stereotactic biopsy was appropriate for direction of clinical management in 28 of 30 patients. Correlation between the stereotactic and resection diagnoses was exact in 19 of 30 cases. These included 11 of 12 nonastrocytic neoplasms and 8 of 13 astrocytic neoplasms. Correlation was imperfect in 9 of 30 cases, but not to the extent of having significant clinical impact. These included 2 cases of anaplastic astrocytoma that were upgraded to glioblastoma multiforme, 2 cases of astrocytoma that had a significant oligodendroglial component, and 5 non-neoplastic lesions that were reported on biopsy as showing nonspecific reactive changes. In 2 of 30 patients, the stereotactic biopsy was not accurate. This included one patient who had glioblastoma multiforme whose stereotactic biopsy showed only necrotic tissue. Serious diagnostic error that resulted in clinical mismanagement occurred in one patient who had a pineal germinoma that had large areas of granulomatous inflammation at which the stereotactic biopsy was directed. This study provides evidence that, with careful target placement, stereotactic biopsy can provide biopsy material that represents the entire lesion with an accuracy that is sufficient for clinical management.

Survival after Stereotactic Biopsy of Malignant Gliomas

For many patients with malignant gliomas in inaccessible or functionally important locations, stereotactic biopsy followed by radiation therapy (RT) may be a more appropriate initial treatment than craniotomy and tumor resection. We studied the long term survival in 91 consecutive patients with malignant gliomas diagnosed by stereotactic biopsy: 64 had glioblastoma multiforme (GBM) and 27 had anaplastic astrocytoma (AA). Sixty-four per cent of the GBMs and 33% of the AAs involved deep or midline cerebral structures. The treatment prescribed after biopsy, the tumor location, the histological findings, and the patient's age at presentation (for AAs) were statistically important factors determining patient survival. If adequate RT (tumor dose of 5000 to 6000 cGy) was not prescribed, the median survival was less than or equal to 11 weeks regardless of tumor histology or location. The median survival for patients with deep or midline tumors who completed RT was similar in AA (19.4 weeks) and GBM (27 weeks) cases. Histology was an important predictor of survival only for patients with adequately treated lobar tumors. The median survival in lobar GBM patients who completed RT was 46.9 weeks, and that in lobar AA patients who completed RT was 129 weeks. Cytoreductive surgery had no statistically significant effect on survival. Among the clinical factors examined, age of less than 40 years at presentation was associated with prolonged survival only in AA patients. Constellations of clinical features, tumor location, histological diagnosis, and treatment prescribed were related to survival time.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of cytologic composition with microfluorometric DNA analysis of the glioblastoma multiforme and anaplastic astrocytoma

The DNA content of selected areas of 16 glioblastoma multiforme predominantly composed of small anaplastic cells was investigated. These findings were contrasted with those of five cases of anaplastic astrocytomas. The microfluorometric determination of DNA was performed on mechanically isolated single cells stained by the Feulgen method, obtained from selected areas of the neoplasms in paraffin blocks. Twelve of 16 cases of glioblastoma multiforme had a main population that was diploid-near diploid. Although four of the five anaplastic astrocytomas disclosed a diploid-near diploid main population there was a more complex DNA distribution than in the small cells in glioblastomas. These differences were evident using two numerical DNA indices obtained from the analysis of each tumor histogram which defined, respectively, the extent to which the main tumor cell population deviated from euploid values and the probabilities to have multiple stemlines with abnormal DNA content. The results suggest that small anaplastic cells which appear to represent the most aggressive population in glioblastomas have a DNA content diploid-near diploid, and in malignant gliomas the degree of aneuploidy of the main stemline is not related to the biologic behavior of the neoplasm.