Multifocal dysembryoplastic neuroepithelial tumor with signs of atypia after regrowth

Abstract

We report the case of a multifocal dysembryoplastic neuroepithelial tumor (DNT) in a 7-year-old girl with local tumor regrowth 6 years later. The tumor was localized in the right parietal lobe extending from the cortex into the periventricular white matter. After subtotal resection of a histopathologically confirmed DNT we observed unexpected tumor progression in long-term follow-up. Therefore, a second surgery was performed when the patient was 14 years of age. In neuropathological examination of the second specimen the tumor showed an increased cellularity and pleomorphism, microvascular proliferations, an elevated proliferative activity (MIB1-index focally up to 10%) and cellular atypia not typical for WHO grade I DNT. Furthermore, MRI studies showed additional supratentorial and infratentorial lesions which remained stable over years and are also well consistent with DNTs. Thus, an unusual form of a DNT with multifocal lesions, local regrowth and morphological transformation is supposed.

Multifocal Dysembryoplastic Neuroepithelial Tumour with Intradural Spinal Cord Lipomas: Report of a Case

“…One paper has expressed doubts as to the neoplastic basis of DNET [5], considering it to represent a hamartomatous anomaly with abnormal arrangements of normal neuronal and glial components. This is not a widely recognized perspective, with cases of malignant transformation [6, 7] and regrowth following subtotal resection [8] supporting the hypothesis that it is a true neoplasm.…”

Multifocal dysembryoplastic neuroepithelial tumours associated with refractory epilepsy

“…Those with multifocal involvement are rare, with only four cases reported in which DNETs occurred in infra-and supra-tentorial locations (Leung et al, 1994;Krossnes et al, 2005;Schittenhelm et al, 2007;White et al, 2011). Typically located in the temporal lobes, DNETs have also been reported within the periventricular white matter, basal ganglia, thalamus, brainstem, and cere-bellum.…”

Dysembryoplastic Neuroepithelial Tumor

“…16 Some aggressiveness criteria, including obvious mitotic figures, increased cellularity and nuclear pleomorphism, significant microvascular proliferation, elevated proliferative activity, and focal leptomeningeal involvement can be observed in a few cases and suggested that these patients need to be more closely followed up. 1,5,17,18 In this study, 1 case (case 3) with increased cellularity and microvascular proliferation and another (case 7) with isolated foci of leptomeningeal involvement and elevated proliferative activity (MIB1 index focally up to 3.6%) developed a recurrence of seizures. The impact of these aggressiveness criteria on patients' long-term outcomes remains to be further studied.…”