P36. The calcium binding proteins S100A8 and S100A9 as novel markers for human prostate cancer

Abstract

Background: Meningiomas are usually benign tumors and cytogenetically well-characterized. Most tumors show either monosomy 22 or a diploid karyotype. Progression of meningiomas is correlated with increasing hypodiploidy and the loss of the short arm of chromosome 1. The aim of this study was to assess intratumoral patterns of clonal chromosomal evolution in order to identify tumor progression pathways and to analyze their correlation with time to recurrence. Methods: From 1973 to 2004, 661 patients with complete tumor resections and cytogenetic characterization were followed up. We have developed oncogenetic trees mixture models for estimating the most likely order of cytogenetic aberrations. Results: Overall, in 8.0% (53/661) of the tumors at least one recurrence was documented during the study. Our results showed a significant correlation between cytogenetic data and recurrence (p < 0.001), location (p < 10 ) and WHO grade (p < 10 ). The estimated model was used to assign a genetic progression score (GPS). The GPS of a tumor is a quantitative measure and allows precise assessment of genetic progression. We classified tumors in three groups with low genetic progression (GPS < 2), intermediate genetic progression (2 6 GPS < 6) and advanced genetic progression (GPS P 6). The recurrence rate is 7.9% (27/343) in the low progression group, 4.0% (11/273) in the medium progression group, and 33.3% (15/45) in the high progression group. Conclusion: Therefore, cytogenetic classification of meningiomas is a powerful tool to predict tumor recurrence and a valuable parameter for the postoperative management protocol.