Caveolin-1 (cav-1) has been proposed as an immunohistochemical marker able to distinguish
astroglial from oligodendroglial tumors. In addition, it has been suggested that the
reduction of caveolin-1 expression in glioblastoma cells increases their proliferative
and invasive potential. Accordingly, the present study investigates caveolin-1 immunoexpression
and correlation with the 1p/19q status, histologic grade, proliferation index, epidermal
growth factor receptor, and p53 expression in a series of 73 diffuse gliomas. A membranous
and cytoplasmic immunolabeling for caveolin-1 was detected in neoplastic cells of
60% of cases. No significant differences in terms of caveolin-1 expression were observed
between astrocytomas, oligodendrogliomas, and oligoastrocytomas. In addition, caveolin-1
expression was not correlated with 1p/19q status in oligodendrogliomas and mixed oligoastrocytomas.
Caveolin-1 was expressed in most high-grade (World Health Organization III and IV)
gliomas. Low caveolin-1 expression correlated with a higher Ki-67 labeling index and
the absence of p53 overexpression in glioblastomas, and it was significantly associated
with epidermal growth factor receptor overexpression in anaplastic astrocytomas. In
conclusion, the present study indicates that caveolin-1 is not useful as diagnostic
marker to differentiate grade II astrocytomas from oligodendrogliomas.