Multiple sclerosis and oligodendroglioma.

Two cases of multiple sclerosis (MS) and oligodendroglioma are reviewed, increasing the total number of reported cases to II. In this series, the clinical onset of MS preceded the discovery of the tumor by a mean of 15 years. No distinguishing features of oligodendroglioma were characteristic of MS-associated cases. However, there was an overrepresentation of benign MS. Although this could result from biased ascertainment, other possibilities, including effective remyelination mediated by mitotically active oligodendrocytes, or secretion of immunosuppressive cytokines by the tumor tissue, cannot be excluded. It is likely that the coexistence of MS and oligodendroglioma is due to chance alone, nonetheless the possibility that glioma derived factors can moderate the disease course in MS is deserving of further study.