CELL KINETIC-ANALYSIS IN RECURRENT NEURO-EPITHELIAL TUMORS

The biological behaviour of brain rumours is variable. Ln the majority of cases, recurrence of the tumour is the decisive factor determining the prognosis and individual survival of patients suffering from a ne uro-epithelial neoplasm. The time course of recurrences varies signifi cantly according to differences in tumour cell proliferation. In this study, predictive factors concerning the expected prognosis following the resection of neuro-epithelial rumours were investigated with the a im of improving the histological diagnosis. A retrospective analysis o f 22 recurrent neuro-epithelial rumours (recurrent tumour group) and 1 2 neuro-epithelial rumours with a minimum survival rate of 5 years fol lowing radical excision (cured tumour group) was performed by means of flow cytometry and immunohistochemistry using the MIB I antibody. His tological samples of the subgroups of the recurrent tumour group, i.e. , the primary rumours and their recurrences were compared with each ot her, and the subgroups were compared with the cured tumour group. A mu ltivariate analysis of the data was performed with the BMPD Hotteling T square test. A statistically significant difference was found betwee n the recurrent tumour group (primary rumours + recurrences) and the c ured group from every investigated aspect. On the other hand, no diffe rence could be found between the subgroups primary rumours and their r ecurrences. All rumours in the recurrent group had an accelerated, act ive cell cycle, which was expressed in a high proliferation activity. The following conclusion was drawn: an increased risk of recurrence is to be expected in neuro-epithelial tumours characterized by: an S-pha se fraction higher than 6-9%, an MIB I-labelled cell number higher tha n 2-3/high-power fields. and a number of mitoses higher than 1/10 high -power fields.