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Microvessel density in
progressive meningiomas and its influence on time to tumour recurrence
C. Marosi, M. Hassler, J. A. Hainfellner, M. Van Trotsenburg, M. Preusser, P.
Birner, J. Berger
University of Vienna, Wien, Austria
Background. Meningiomas constitute circumscribed intracranial tumours of
limited resectability.
Adjuvant therapy is applied for growth control of incompletely resected
tumours.
However, radiotherapy is limited for tumours in certain locations due to the
presence of adjacent radiosensitive neural structures.
In such cases, chemotherapy is mandatory for tumour control, but hitherto used
chemotherapy protocols showed unsatisfactory therapeutic effects.
Methods. In order to develop new approaches based upon angiogenetic
properties, we analysed systematically tumour vascularization in a set of 26
recurrent or inoperable meningiomas of 13 patients using the endothelial cell
marker anti-CD34 for immunostaining.
We determined microvessel density (MVD) within the tumour area with the highest
vessel density by counting all anti-CD34 immunostained vessels at a
magnification of x 200 within an examination area of 0.25 mm2 using
an eye grid.
Further, we analysed expression of vascular endothelial growth factor (VEGF) at
the messenger RNA and protein levels.
Results. MVD ranged from 22 to 149 vessels/standard area with a median of
50.5.
Focal or widespread expression of VEGF messenger RNA was detectable in 17/19
analysed samples and VEGF protein expression was observed in all tumour
samples.
Clinically, the time to recurrence of tumours with high ( ≥ 50.5) MVD (
28.4 months) was significantly shorter as compared to tumours with low MVD (
72.1 months; p = 0.0136).
Conclusions. Our data indicate that MVD may influence the progression of
meningiomas.
Due to the expression of VEGF messenger RNA and / or VEGF protein in all tumour
samples, anti-VEGF strategies may exert a beneficial therapeutic effect in
progressive meningiomas.
Copyright 2004 American Society of Clinical Oncology All rights
reserved worldwide.
Source: http://www.asco.org/ac/1,1003,_12-002636-00_18-0026-00_19-00501,00.asp
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