DETERMINATION OF GROWTH FRACTION AND CELL-DENSITY TO EVALUATE THE POTENTIAL GROWTH OF HUMAN OLIGODENDROGLIAL AND ASTROCYTIC TUMORS

The object of this work was Purpose: to develop a methodology that ena bles net tumour growth, a balance between actual tumour growth and tum our cell loss, to be approximately evaluated. Methods: The methodology proposed relies on detecting the growth fraction immunohistochemicall y by means of MIB-1 antibody labelling combined with cell density dete rmination, carried out on 5-mu m-thick Feulgen-stained histological se ctions with computer-assisted microscopy. The series investigated incl uded 25 oligodendrogliomas (OLG-II), 9 anaplastic oligodendrogliomas ( OLG-III), 13 astrocytomas (AST), 14 anaplastic astrocytomas (ANA) and 8 mixed oligoastrocytomas (OLG-AST). Results: The results show that th e biological characteristics of some cases were in total accordance wi th their histopathological diagnoses. This was the case for the ''weak ly proliferating weakly dense'' OLG-II and AST-II tumours, and for the ''highly proliferating highly dense'' OLG-III and AST-III ones. In co ntrast, the biological characteristics of some cases seemed to contrad ict the histopathological case labels. This was the case for the ''hig hly proliferating highly dense'' OLG-II and AST-II tumours, the biolog ical aggressiveness of which would be undervalued on the basis of the morphology-based grading system alone, and also for the ''weakly proli ferating weakly dense'' OLG-III and AST-III tumours, the aggressivenes s of which would be overvalued. Conclusions: Combining the determinati ons of the MIBI and the cell density variables appears to be satisfact ory in terms of the cell kinetic characterization of glial tumours as a complement to the prognostic information given by a morphology-based grading System alone.