Indications and limits of intraoperative cortico-subcortical mapping in brain tumor surgery: an analysis of 101...

Here we report our recent experience in supratentorial cortico-subcortical stimulation mapping during surgery for cerebral lesions closely related to sensorimotor and language areas.

We retrospectively analyzed clinical data of 101 consecutive patients operated on with the aid of electrical stimulation mapping (ESM). Patients harbored a mass lesion situated in or near language (Group A, 30 patients) and sensorimotor (Group B, 71 patients) areas.

A macroscopically complete removal of the tumor was carried out in 22 cases out of 28 of group A and in 57 out of 73 of group B. In the first group there was one postoperative death due to a pulmonary embolism. At a mean follow-up of 24.3 months, 15 patients are still alive, 12 out of them are recurrence free and hold a useful language function, while the other 12 patients had a mean survival time of 19.3 months, with a mean high quality survival period (KPS?70) of 17.8 months. In the second group there was no postoperative death. At a mean follow-up of 24.8 months, 55 patients are alive and 47 maintain a useful motor function. Eighteen patients died for tumor progression, with a mean survival time of 18.7 months. Their median high-quality survival period (KPS ? 70), with preservation of a useful motor function, was 16.5 months.

When properly indicated and correctly carried out, ESM for language and motor functions allows to enhance resection of lesions in eloquent areas with a surgical permanent morbidity comparable to that for lesion in non eloquent areas.