Turkish Neurosurgery 2001 , Vol 11 , Num 1-2
THE IMPORTANCE OF FLOW CYTOMETRIC DNA ANALYSIS IN GLIAL TUMORS
Celal BAĞDATOĞLU1, Gökalp SİLAV2, Arzu KANIK3, Habibullah DOLGUN2, Gülşah BADEMCİ2, Haluk DEDA2
1Mersin University, Faculty of Medicine, Department of Neurosurgery, Mersin
2Ankara University Faculty of Medicine Department of Neurosurgery, Ankara
3University of Mersin Faculty of Medicine, Department of Biostatistics, Mersin
Neoplasms of glial origin constitute 40-50% of all primary tumors of the central nervous system. Although a number of clinical features are related to prognosis, tumor grade is currently used to predict outcome. However, at present, grading is a subjective process based on tumor morphology and quantitation of microscopic features such as cellularity, cytologic atypia, mitotic figures, and endothelial proliferation. Distinguishing between low- and high-grade lesions is sometimes subjective, and results may vary depending on the observer. We studied fresh tissue samples that were surgicaııy resected from 30 patients (l6 males, 14 females) between April 1996 and Febrtıary 19S18. Patient age ranged from 6 to 73 years, and the mean age was 43.7 years. Pathologic examination revealed 3 pilocytic astrocytomas, 3 grade I astrocytomas, 10 grade II astrocytomas, 9 grade IV astrocytomas, 2 malignant ependymomas, and 3 oligodendrogliomas. We studied relationships between patient survival time and tumor ploidy, patient age, S-phase, and histological subtype. Follow-up ranged from 2 to 31 months, with an average of 13.1 months. Sixteen of the 30 tumors were aneuploid (53.3%) and 14 were diploid (46.7%). The mean coefficient of variation value was 4.36%. Patients with diploid cell populations had a longer period of disease-free survival compared to those with aneuploid cell populations. Also, individuals with low S-phase fractions survived longer than individuals with higher S-phase fractions. The study showed that patient survival time was correlated with DNA ploidy, histological subtype (except the grade II astracytomas), and S-phase fraction, but there was no correlation between survival time and patient age. In our study, besides histologic subtype, flow cytometric DNA analysis is found to be necessary for determining prognosis in glial tumors. Keywords : Flow cytometry, glial tumors, prognosis
Corresponding author : Celal Bagdatoğlu