chapter  29
Dysembryoplastic neuroepithelial tumor
ByMarc K. Rosenblum
Pages 12

Characterized as a distinct clinicopathologic entity by Daumas-Duport and coworkers (1988), the dysembryoplastic neuroepithelial tumor (DNT) is presently classified as a WHO Grade I neoplasm of mixed glioneuronal type (Daumas-Duport et al., 2000). In retrospect, an account by Cavanagh (1958) of ‘certain small tumours encountered in the temporal lobes’ of patients with longstanding epilepsy would appear to include lesions recognizable as DNTs. The generic designation of these unusual growths as ‘neuroepithelial’ was chosen to acknowledge the apparent participation of oligodendroglial, astrocytic, and neuronal forms in their development, while the qualifying ‘dysembryoplastic’ was prompted by their frequent association with cerebrocortical microanomalies taken as evidence for a promoting process of maldevelopmental nature (Daumas-Duport et al., 1988). Since publication of the groundbreaking observations made by Daumas-Duport and colleagues, the clinicopathologic features of the DNT have been profiled in a number of series and reviews (Daumas-Duport, 1993; Raymond et al., 1994; Taratuto et al., 1995; Wolf et al., 1995; Prayson et al., 1996; Honavar et al., 1999; Daumas-Duport et al., 2000). Whether the polymorphous lesions yoked, in the cited literature, under the designation of DNT all merit acceptance as representatives of a unified entity may be questioned. Conversely, it would appear that at least some cerebral neoplasms described as ‘neurocytomas’ or variants thereof actually conform more closely to DNTs in their

topographic and histologic characteristics (Nishio et al., 1992).