Anaplastic ganglioglioma with sarcomatous component: an immunohistochemical study and molecular analysis of p53 tumor suppressor gene.

The present case report describes a case of ganglioglioma with a distinct sarcomatous component in the left temporal lobe of a 59-year-old Japanese man. Neoplastic neuroglial tissue contained both benign and anaplastic glial components with a MIB-1 labeling index of 0.1% and 12.0%, respectively. Sarcomatous tissue adjacent to the anaplastic glial tissue was dominated by pleomorphic fibroblastic cells with a MIB-1 labeling index of 10.8%. They were immunoreactive for smooth muscle actin, type IV collagen, and alpha 1 antitrypsin, but not for desmin and CD34. Interestingly, some of the sarcomatous cells were double-positive for smooth muscle actin and GFAP. The p53 protein had accumulated in the anaplastic astrocytes and sarcomatous cells, but direct DNA sequencing of PCR products failed to detect any mutation in the p53 gene (from exon 4 to exon 10).