CORRELATION OF DNA CONTENT AND NUCLEOMORPHOMETRIC FEATURES WITH WORLD-HEALTH-ORGANIZATION GRADING OF MENINGIOMAS

Many studies dealing with extracranial cancer showed a strong correlat ion of DNA ploidy to a poor clinical outcome, recurrence, or malignanc y, In brain tumors, analysis of DNA content did not always provided si gnificant diagnostic information. In this study, DNA density and karyo metric parameters of 50 meningiomas (26 Grade I, 10 Grade II, 14 Grade III) were quantitatively evaluated by digital cell image analyses of Feulgen-stained nuclei. In particular, the densitometric parameter SEX T, which describes nuclear DNA content, as well as the morphometric va lues LENG (a computer-assisted measurement of nuclear circumference), AREA (a computer-assisted measurement of nuclear area), FCON (a parame ter that describes nuclear roundness), and GONG (a describing nuclear contour), evaluated with the software IMAGE C, were correlated to Worl d Health Organization (WHO) grading using univariate and multivariate methods. AREA and LENG values showed significant differences between t umors of Grades I and III, FCON values were unable to distinguish WHO Grade III from Grade I/II but were useful in clearly separating Grade II from Grade I tumors. GONG values detected differences between WHO G rades II and I/III tumors but not between the latter, SEXT values clea rly distinguished Grade III from Grade I/II tumors. The 1c, 2c, 2.5c, and 5c exceeding rates showed no predictive values. Only the 6c exceed ing rate showed a significant difference between Grades I and III. The se results outline the characteristic features of the atypical (Grade II) meningiomas, which make them a recognizable tumor entity distinct from benign and anaplastic meningiomas, The combination of DNA densito metric and morphometric findings seems to be powerful addition to the histopathologic classification of meningiomas, as suggested by the WHO .