Apoptosis in metastatic carcinoma of the central nervous system

High apoptotic indices have been described in pseud-opalisading areas of glioblastoma multiforme (astrocytoma grade 4). In order to explore further the role of apoptosis in regulating the proliferation in central nervous system (CNS) tumors, we used TdT-mediated dUTP-nick endlabeling (TUNEL) methods to compare the frequency and distribution of apoptotic cells in 32 cases of metastatic carcinoma and 54 cases of primary diffuse astrocytomas. Frequencies of apoptotic cells and Bcl-2 positive cells in metastatic carcinoma were low compared with those observed in high-grade diffuse astrocytomas and did not correlate with the expression of the p53 protein. These findings suggest that apoptosis does not have a major role in regulating proliferation in metastatic carcinoma of the CNS.