Functionality of glioma-infiltrated precentral gyrus: experience from 14 patients.

Background: In this study we reviewed our experience with surgical removal of gliomas that infiltrated the precentral gyrus.

Methods: From a consecutive series of 100 patients that were operated with intraoperative monitoring, 14 patients were retrospectively selected and analyzed for results of (sub)cortical electrical stimulation, extent of resection and temporary or permanent neurological deficits.

Results: In 10 of 14 patients there were no neurological deficits prior to surgery despite tumor-infiltrated precentral gyrus. Resection of these tumors was (severely) limited in 6 patients due to cortical or subcortical responses from precentral gyrus or corticospinal tract. These responses reflected limb or speech/language functions. In 2 patients the tumor was not resected or only partially removed due to the confounding influence of seizures during the operation. Overall, 4 tumors were completely resected. In one patient this resulted in a new and permanent minor motor deficit of the foot.

Conclusions: We conclude from our study that the chance that a glioma can be resected from the upper parts of the precentral gyrus is low, especially in those cases where tumor margins are diffuse. Possible exceptions are gliomas that are hypointense on T1-weighted images and have sharp margins; these patients should a priori not be excluded from surgery. We could confirm previous reports in the literature that gliomas in the face area of the non-dominant hemisphere can be resected without permanent morbidity.