Instability of mitochondrial DNA and MRI and clinical correlations in malignant gliomas.

Mutations and instability of mitochondrial DNA (mtDNA) are frequent in tumors but their pathogenic relevance is not established. To assess their role in the clinical management of malignant gliomas we have studied the D loop of mtDNA in 42 such tumors. Alterations were found in 36 of the cases. The MRI and the clinical follow-up of these patients suggest that these mutations are not associated with increased aggressiveness. mtDNA could be amplified from post-surgical tumor cavities in patients undergoing a loco-regional treatment. These results imply that mtDNA mutations are unlikely to play a role in diagnostic or prognostic evaluations of gliomas:their detection, however, could be of use for the clinical follow-up of malignant gliomas.