Surgery of highly eloquent gliomas primarily assessed as non-resectable: risks and benefits in a cohort study

Abstract

BackgroundToday, the treatment of choice for high- and low-grade gliomas requires primarily surgical resection to achieve the best survival and quality of life. Nevertheless, many gliomas within highly eloquent cortical regions, e.g., insula, rolandic, and left perisylvian cortex, still do not undergo surgery because of the impending risk of surgery-related deficits at some centers. However, pre and intraoperative brain mapping, intraoperative neuromonitoring (IOM), and awake surgery increase safety, which allows resection of most of these tumors with a considerably low rate of postoperatively new deficits.MethodsBetween 2006 and 2012, we resected 47 out of 51 supratentorial gliomas (92%), which were primarily evaluated to be non-resectable during previous presentation at another neurosurgical department. Out of these, 25 were glioblastomas WHO grade IV (53%), 14 were anaplastic astrocytomas WHO grade III (30%), 7 were diffuse astrocytomas WHO grade II (15%), and one was a pilocytic astrocytoma WHO grade I (2%). All data, including pre and intraoperative brain mapping and monitoring (IOM) by motor evoked potentials (MEPs) were reviewed and related to the postoperative outcome.ResultsAwake surgery was performed in 8 cases (17%). IOM was required in 38 cases (81%) and was stable in 18 cases (47%), whereas MEPs changed the surgical strategy in 10 cases (26%). Thereby, gross total resection was achieved in 35 cases (74%). Postoperatively, 17 of 47 patients (36%) had a new motor or language deficit, which remained permanent in 8.5% (4 patients). Progression-free follow-up was 11.3 months (range: 2 weeks – 64.5 months) and median survival was 14.8 months (range: 4 weeks – 20.5 months). Median Karnofsky Performance Scale was 85 before and 80 after surgery).ConclusionsIn specialized centers, most highly eloquent gliomas are eligible for surgical resection with an acceptable rate of surgery-related deficits; therefore, they should be referred to specialized centers.

Multimodal Imaging in Malignant Brain Tumors: Enhancing the Preoperative Risk Evaluation for Motor Deficits with a Combined Hybrid MRI-PET and Navigated Transcranial Magnetic Stimulation Approach

“…30 However, both T1-CE and FET-PET were of equal value for the prediction of postoperative functional outcome: While the absence of overlap with functional tissue maps predicted a favorable outcome, the presence of overlap before the operation was associated with a considerably higher risk of motor deterioration after the operation (33%) compared with the risk of the entire sample (14%) or with the risk reported in the literature, ranging from 6% to 19%. [3][4][5] These findings need to be confirmed in a larger series but may be of great value in more wisely selecting and advising patients with brain tumors in the proximity of the CST or M1 for operative tumor removal. Not surprising, the sensitivity of either FET-PET or T1-CE in revealing motor deficits before the operation was limited.…”

“…2 A frequently encountered phenomenon in patients presenting with tumors in the vicinity of motor regions is that some of them have motor impairment while others do not, and some deteriorate after the operation while others may even improve. [3][4][5] In some patients, motor deficits can be explained by direct infiltration of the tumor into the motor cortex or corticospinal tract (CST), while in other patients, compression effects resulting from the tumor mass and/or perifocal edema may cause motor symptoms. 5 Differentiating causes is, however, highly relevant with respect to the reversibility of symptoms and planning of operations.…”

A Systematic Review and Meta-Analysis of Studies Examining the Use of Brain Laser Interstitial Thermal Therapy versus Craniotomy for the Treatment of High-Grade Tumors in or near Areas of Eloquence: An Examination of the Extent of Resection and Major Complication Rates Associated with Each Type of Surgery

“…There were 19 studies identified using craniotomy [3,4,7,9,10,11,12,32,33,34,35,36,37,38,39,40,41,42,43]. Of these, 6 articles were excluded [3,32,37,42,43] due to an inability to break out complications related to surgery in areas of eloquence.…”

“…It was found that 3 such complications occurred in these studies (table 2). There were 11 craniotomy studies totaling 1,036 patients included in this analysis [3,9,10,11,12,34,35,36,39,40,41]. There were 141 such complications that occurred (table 2).…”

Intraoperative Monitoring with Cortical Estimulation

“…The correct surgical planning for radical resection of gliomas allows a better quality of life and increases patient survival 13,[24][25][26][27][28] . However, there is a potentially high risk of permanent sequelae, particularly when the tumor is located within eloquent brain regions.…”