STEREOTAXIC BIOPSIES FROM ASTROCYTIC TUMORS - DIAGNOSTIC INFORMATION CONTRIBUTED BY THE QUANTITATIVE CHROMATIN PATTERN DESCRIPTION

OBJECTIVE: To reduce the problem of heterogeneity in astrocytic tumors by means of computer-assisted microscope analysis of Feulgen-stained nuclei. STUDY DESIGN: Thirty-eight glial tumors for which we obtained 227 stereotactic biopsies were subjected to digital cell image analysi s of Feulgen-stained nuclei. This series of 38 glial tumors included 3 6 supratentorial astrocytic tumors (13 astrocytomas, 7 anaplastic astr ocytomas and 16 glioblastoma multiformes) and 2 grade 3 astrocytic tum ors of the cerebellum. RESULTS: The results suggest a new methodology, enabling the biologic characteristics of the brain parenchymal area s urrounding a given glial tumor to be characterized. This methodology r elies on the performance of three successive steps. The first is quant itative characterization of nuclear morphology and its chromatin patte rn by means of 15 morphonuclear variables. This characterization is ca rried out by means of the computer-assisted microscope analysis of Feu lgen-stained nuclei. The second step consists of setting up morphonucl ear data banks, with each process giving the precise portrait of a giv en cell nuclear population. This process is carried out by means of mu ltivariate analysis, taking into account the 15 variables mentioned ab ove. Multivariate analysis includes principal components analysis foll owed by the canonical transformation of the data. The third step consi sts of testing unknown cases against these morphonuclear data banks. T his is carried out by means of linear discriminant analysis, which ena bles the various cell nuclear types in the stereotactic biopsy to be q uantified. CONCLUSION: The present methodology makes if possible to in vestigate whether infiltrating tumor cells are present in or absent fr om the parenchymal brain area surrounding a glial tumor. It can theref ore contribute additional information to that contributed by computed tomography and/or magnetic resonance imaging with respect to the preci se delineation of the volume of a brain tumor. This delineation must b e as precise as possible to allow total surgical resection of the tumo r and prevention of its recurrence.