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PubMed · 12630077

Topometric analysis of diffuse astrocytomas.

Abstract

OBJECTIVE: To investigate differences between astrocytomas of WHO grade 2 and anaplastic astrocytomas of WHO grade 3 in terms of topometric variables characterizing individual tumor cell nuclei. STUDY DESIGN: Paraffin sections from surgical specimens from 25 astrocytomas (grade 2, n = 11; grade 3, n = 14) were analyzed by means of an image analysis system. At least 300 tumor cell nuclei were measured in the region with the highest Ki-67 proliferation index. Three different kinds of topometric variables were determined for each tumor cell nucleus: (1) several distances; (2) the variable Angle 2/1, the angle between the straight lines representing the distance to the nearest and second-nearest nucleus; and (3) the number of neighbors according to our mathematical definition. RESULTS: Most topometric variables showed distinct differences between the 2 tumor grades (multivariate analysis of variance), with 88% cases correctly reclassified by means of cross-validated discriminant analysis. The variables with the highest discriminatory power were the SD of Angle 2/1 and the ratio between the distance to the second-nearest and nearest tumor cell nucleus, with lower values for these variables in anaplastic astrocytomas. Even variables concerning neighborhood relationships showed significant differences. CONCLUSION: The results of this pilot study show that this first set of topometric variables is sufficient to detect differences between topologic characteristics of tumor cell nuclei in astrocytomas grade 2 and grade 3. Topometry seems to be an important tool for grading astrocytomas.

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Reinhold Nafe, Wolfgang Schlote. 2003. Topometric analysis of diffuse astrocytomas.. https://pubmed.ncbi.nlm.nih.gov/12630077/

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