ABSTRACT
BACKGROUND: About 10% of meningiomas behave aggressively and are graded atypical or malignant with important therapeutic and prognostic implications. Routine histological parameters are inconsistent in the assessment of their aggressive behavior. AIMS: The aim of this study was to find a threshold level of the MIB-1 labeling index (MIB-1 LI) with the highest diagnostic validity in predicting histological atypia in a meningioma. SETTING AND DESIGN: This was a retrospective study of all atypical and malignant meningiomas diagnosed at our center between January 1995 and June 2000 and which were identified from the General Pathology Registry. MATERIAL AND METHODS: These meningiomas were assessed histologically with respect to the individual criteria of atypia. They were categorized according to the WHO 2000 classification as benign, atypical and anaplastic meningiomas, WHO Grades I, II and III respectively and by immunohistochemical analysis using the MIB-1 monoclonal antibody. STATISTICAL ANALYSIS: The diagnostically useful cut-off level for the prediction of atypia was estimated by calculating the sensitivity and specificity of the MIB-1 LI at various levels and a receiver operated characteristic (ROC) analysis was performed. The correlation between the individual histological parameters was studied and the MIB-1 LI was obtained using Fisher's exact test. RESULTS: Of the 40 meningiomas studied 21 were benign, 16 atypical and 3 anaplastic. Atypical tumors had a higher MIB-1 LI than benign tumors, with diagnostic validity highest at a threshold of 7%, with a sensitivity of 0.86 and a specificity of 0.93, giving a likelihood ratio of 17. The MIB-1 LI correlated well with mitotic activity and the other individual criteria in the WHO 2000 definition of atypia in a meningioma. MIB-1 LI did not, however, correlate well with brain invasion. CONCLUSION: The MIB-1 LI has the highest validity in the diagnosis of atypia in meningiomas at a threshold level of 7%. The MIB-1 LI used in conjunction with histological features can help in making a recommendation regarding potentially aggressive behavior in meningiomas.
Subject(s)
Adolescent , Adult , Aged , Antibodies, Antinuclear/diagnosis , Antibodies, Monoclonal/diagnosis , Female , Humans , Immunohistochemistry/methods , Ki-67 Antigen/analysis , Male , Meningeal Neoplasms/chemistry , Meningioma/chemistry , Middle Aged , Reproducibility of Results , Retrospective StudiesABSTRACT
The authors assessed 116 cases of meningiomas classified as typical, atypical and anaplastic and they used an immunohistochemical technique for estrogen and progesterone receptors attempting to determine if there is any difference between typical and non-typical tumors in relation to hormone receptors. The immunohistochemical technique to estrogen receptors was negative in all meningiomas studied. Progesterone receptors were detected in 58.3 percent of typical, and in 48.2 percent of non-typical meningiomas. This difference was not statistically significant. However, individually considering the criteria used for selection of non-typical tumours, those that concurrently displayed brain invasion and increased mitotic activity or necrosis, as well as the summation of those three features, were predominantly negative for progesterone receptors (respectively p=0.038; p=0.001; and p=0.044). The authors conclude that estrogen receptors were not present in meningiomas; that progesterone receptors in isolation are not enough to predict a higher tumoral malignancy but can be useful associated with other histological features.
Subject(s)
Humans , Male , Female , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Meningeal Neoplasms/chemistry , Meningioma/chemistry , Receptors, Estrogen/analysis , Receptors, Progesterone/analysis , Aged, 80 and over , Meningeal Neoplasms/immunology , Meningioma/immunology , Random AllocationABSTRACT
A case of spinal meningeal melanocytoma is reported along with clinicopathologic, immunohistochemical and ultrastructural studies. This patient presented clinically with paraparesis, tingling sensation and numbness of both lower extremities of 4 months duration. No mucocutaneous pigmented nevi were found. On operation, scattered coal-black pigmented lesions were found in the meninges between T3 and T4-5 interspace level. Nearly total removal was carried out. The tumor was composed of spindle and epithelioid cells with heavy brown-black pigmentation. There was no pleomorphism, mitosis, hemorrhage, necrosis or invasion to the underlying cord tissue. In Korea, this case appears to be the first example of this disease. Neurologic deficit improved after surgical excision.