DNA-flow fluorescence ? Cytometry of ependymomas

Abstract

The distribution of DNA is estimated from flow cytometric histograms in surgical specimens of ten ependymomas of different location and varying anaplasia. In three cerebral tumours grade I--II, including one ependymoma of the 4th ventricle, only limited elevation of the 4 C maxima was a prominent feature, corresponding to the microscopical frequency of typical mitoses. Four grade-III ependymomas showed aneuploid or polyploid histograms with stem lines. One frontal tumour was classified as "transitional" because of more numerous mitoses and abnormally elevated S and G2 + M phases, which increased in tissue culture. A correlation between the degree of anaplasia with the DNA pattern was difficult to pursue in two spinal ependymomas obviously lacking microscopical mitoses: Both--one a so-called tanycytic variant of grade I--II, and the other probably a metastasis from a cerebellar tumour--had a clear polyploid DNA histogram with a strikingly increased proliferation index, similar to the more malignant tumours of grade III. Also flow DNA measurements probably allow the decoding of heterogenous mixtures of tumour cells which are not always benign in ependymomas of lower grades of anaplasia microscopically.

Pediatric Intracranial Ependymomas: Prognostic Relevance of Histological, Immunohistochemical, and Flow Cytometric Factors

“…Kotylo et al (44) observed an association of diploid DNA stemline with shortened survival in a group of 17 pediatric patients. Spaar et al (45) found aneuploid or polyploid histograms in four anaplastic ependymomas, whereas no association between the ploidy status and the outcome of 22 patients was observed by Reyes-Mugica et al (46). The lack of association of the ploidy and the outcome of the disease was also demonstrated in our series.…”

DNA and prognosis of meningiomas: a comparative cytological and fluorescence-cytophotometrical study of 71 tumours

“…Thus, abnormal DNA distribution in gliomas and paragliomas is probably less related to the histogenetic tumour species than to the degree of its maturation and its morphological anaplasia, respectivelyl, 6, 7, 10, ll, 13,18 For meningiomas, a grade scale of malignancy has been proposed on a microscopic basis 22. Frederiksen et al 7 observed marked differences of the 4 C peaks in tumour DNA histograms.…”

“…Hence, they separated meningiomas with an uneventful diploid DNA pattern (4 C: 5%) from those with slightly (4C up to 10%) or markedly increased (4C: 10-25%) peaks of the G 2 + M area. Others, however, reported only noncontributory diploid karyograms [17][18][19][20] preferred an evaluation of the S-phase cells, which in their "benign type 1" is low (S < 2%), in still benign type 2 (S > 2%) means a risk of tumour relapse, and which in their "unstable, aneuploid type 3" (S > 4%) is correlated with malignant transformation. In our experience, the G 2 + M fractions in the 4 C area exhibit more frequently striking variations than the S-phase compartment; they are therefore probably of greater prognostic relevance in meningiomas.…”

Spinal Tanycytic Ependymoma With Hematomyelia-Case Report-

“…2,4,6,8,10,11,13,14) Only six of the 22 cases of tanycytic ependymoma were thè`p ure type'' and all six arose in the spinal cord. 4,8,11) The six patients were four women and two men aged from 35 to 58 years (mean 46.8 years).…”