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Cytogenetic findings in six recurrent meningiomas
Abstracts
FLOWCYTOMETRIC DNA-ANALYSIS OF MENINGIOMAS J. MEIXENSBERGER, M. Janka, A. Zellner, *M. POOT, **W. ROGGENDORF Neurochirurgische Klinik, *lnstitut for Humangenetik, ** Abteilung for Neuropathologie der Universit~t W0rzburg
Our study attempts to answer following questions: 1. Is there an alteration of the DNA content in meningiomas? 2. Are there differences between tumors of different clinical behaviour? 3. Does a correlation exist between DNA alterations and tumour biology? Tumour tissue of 86 benign meningiomas (including 17 recurrent tumours) were analyzed by flow cytometry after staining with DAPI. By this a number of 25 tumours were aneuploid (30%). Analyzing the diploidy index (DI), we found a significant different DI between primary and recurrent meningiomas (p<0.01). Comparing the mitotic activity of meningiomas, the diploidy index increases significantly with mitotic activity (p<0.01). Additionally, the percentage of G2and S-phase cells in both aneuploid and diploid populations are significantly increased in recurrent meningiomas (P<0.05). As a result of our study, we believe that Flowcytometric analysis can correlate DNA alterations in meningiomas with different clinical stages. The determination of the diploidy index and the % S-phase cells may serve as clinical and prognostic markers for an estimation of the biological validity of meningiomas.
CYTOGENETIC FINDINGS IN SIX RECURRENT MENINGIOMAS ~ , M. Cerdd-Nicolds, JA. Barcia, A. Llombart-Bosch Department of Pathology, Medical School, University of Valencia, Spain.
Meningioma is a primary tumor of the meninges that generally follows a benign clinical course and is usually permanently cured by surgical excision. Clinically, meningiomas recur because of their own biological aggressively, which is expressed phenotypically in malignant and atypical meningiomas, or due to an incomplete surgical resection. The most common chromosomal abnormality observed in meningiomas is monosomy 22. Cytogenetically normal karyotypes are also often found in this type of brain tumor. Karyotypic evolution with loss and/or rearrangement of chromosomes other than chromosome 22 appears to be associated with a more aggressive clinical course. We have analyzed cytogenetically six recurrent meningiomas, one of these with infiltration of the cerebral cortex. Cytogenetic analysis was performed on direct preparations or from tissue culture after 3-10 days. Chromosomal analysis showed the following results: one case had a normal karyotype; one had only monosomy 22; three cases were found with monosomy 22, monosomies of other chromosomes and structural abnormalities with predominant implications of chromosome 1 ; the last cases did not present monosomy 22, but showed other numerical and structural abnormalities. We discuss the relation of these results with the clinical and histopathological characteristics of these recurrent tumors.
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FLOWCYTOMETRIC DNA-ANALYSIS OF MENINGIOMAS J. MEIXENSBERGER, M. Janka, A. Zellner, *M. POOT, **W. ROGGENDORF Neurochirurgische Klinik, *lnstitut for Humangenetik, ** Abteilung for Neuropathologie der Universit~t W0rzburg
Our study attempts to answer following questions: 1. Is there an alteration of the DNA content in meningiomas? 2. Are there differences between tumors of different clinical behaviour? 3. Does a correlation exist between DNA alterations and tumour biology? Tumour tissue of 86 benign meningiomas (including 17 recurrent tumours) were analyzed by flow cytometry after staining with DAPI. By this a number of 25 tumours were aneuploid (30%). Analyzing the diploidy index (DI), we found a significant different DI between primary and recurrent meningiomas (p<0.01). Comparing the mitotic activity of meningiomas, the diploidy index increases significantly with mitotic activity (p<0.01). Additionally, the percentage of G2and S-phase cells in both aneuploid and diploid populations are significantly increased in recurrent meningiomas (P<0.05). As a result of our study, we believe that Flowcytometric analysis can correlate DNA alterations in meningiomas with different clinical stages. The determination of the diploidy index and the % S-phase cells may serve as clinical and prognostic markers for an estimation of the biological validity of meningiomas.
CYTOGENETIC FINDINGS IN SIX RECURRENT MENINGIOMAS ~ , M. Cerdd-Nicolds, JA. Barcia, A. Llombart-Bosch Department of Pathology, Medical School, University of Valencia, Spain.
Meningioma is a primary tumor of the meninges that generally follows a benign clinical course and is usually permanently cured by surgical excision. Clinically, meningiomas recur because of their own biological aggressively, which is expressed phenotypically in malignant and atypical meningiomas, or due to an incomplete surgical resection. The most common chromosomal abnormality observed in meningiomas is monosomy 22. Cytogenetically normal karyotypes are also often found in this type of brain tumor. Karyotypic evolution with loss and/or rearrangement of chromosomes other than chromosome 22 appears to be associated with a more aggressive clinical course. We have analyzed cytogenetically six recurrent meningiomas, one of these with infiltration of the cerebral cortex. Cytogenetic analysis was performed on direct preparations or from tissue culture after 3-10 days. Chromosomal analysis showed the following results: one case had a normal karyotype; one had only monosomy 22; three cases were found with monosomy 22, monosomies of other chromosomes and structural abnormalities with predominant implications of chromosome 1 ; the last cases did not present monosomy 22, but showed other numerical and structural abnormalities. We discuss the relation of these results with the clinical and histopathological characteristics of these recurrent tumors.
173