Surgical removal of corpus callosum infiltrated by low-grade glioma: functional outcome and oncological considerations.

OBJECT: Although still controversial, many authors currently advocate extensive resection in the treatment of low-grade gliomas (LGGs). Because these tumors usually migrate along white matter pathways, the corpus callosum is often invaded. Nevertheless, there is evidently no specific study featuring resection of the corpus callosum infiltrated by glioma, despite abundant literature concerning callosotomy in epilepsy surgery or transcallosal ventricular approaches. The aim of this paper was to analyze functional outcome following removal of corpus callosum invaded by LGG and to analyze the impact of this callosectomy on the quality of resection.
METHODS: Between 1996 and 2002, a total of 32 patients harboring an LGG involving part of the corpus callosum and having no or only a mild preoperative deficit underwent surgery aided by intraoperative electrical mapping to preserve eloquent structures identified on stimulation and to perform the most extensive resection possible. Preoperatively, no clinical response was elicited on stimulation of the corpus callosum; thus, the part of this structure that was invaded by LGG was removed. Despite immediate postoperative neurological worsening, all patients but one recovered within 3 months and returned to a normal socioprofessional life. The additional callosectomy allowed for nine total resections, 18 subtotal resections, and five partial resections. Furthermore, only two cases of contralateral hemispherical migration occurred during a median follow up of 3 years.
CONCLUSIONS: Resection of the corpus callosum infiltrated by glioma improves the quality of tumor removal without increasing the risk of sequelae.