Importance and Evidence of Extent of Resection in Glioblastoma

Abstract

Maximal safe resection is an essential part of the multidisciplinary care of patients with glioblastoma. A growing body of data shows that gross total resection is an independent prognostic factor associated with improved clinical outcome. The relationship between extent of glioblastoma (GB) resection and clinical benefit depends critically on the balance between cytoreduction and avoiding neurologic morbidity. The definition of the extent of tumor resection, how this is best measured pre- and postoperatively, and its relation to volume of residual tumor is still discussed. We review the literature supporting extent of resection in GB, highlighting the importance of a standardized definition and measurement of extent of resection to allow greater collaboration in research projects and trials. Recent developments in neurosurgical techniques and technologies focused on maximizing extent of resection and safety are discussed.

Defining the Impact of Adjuvant Treatment on the Prognosis of Patients with Inoperable Glioblastoma Undergoing Biopsy-only: Does the Survival Benefit Outweigh the Treatment Effort?

“…Until now, no association between localization and tumor subtype has been determined and therefore, further strati cation for tumor subtype and tumor treatment might have been a valuable addition. The presence of IDH-mutation and MGMT promotor methylation are well-established molecular markers associated with a favorable outcome [4,25]. In our study, only the presence of IDH-mutation was independently associated with longer OS.…”

Defining the impact of adjuvant treatment on the prognosis of patients with inoperable glioblastoma undergoing biopsy only: does the survival benefit outweigh the treatment effort?

“…Until now, no association between localization and tumor subtype has been determined; and therefore, further stratification for tumor subtype and tumor treatment might have been a valuable addition. The presence of IDH mutation and MGMT promoter methylation are well-established molecular markers associated with a favorable outcome [ 4 , 26 ]. In our study, only the presence of IDH mutation was independently associated with longer OS.…”

Does positive MGMT methylation outbalance the limitation of subtotal resection in glioblastoma IDH-wildtype patients?

“…Several surgical adjuncts can help to optimize the extent of resection without causing permanent post-op neurological deficits. They include intraoperative neuromonitoring with cortical and subcortical mapping, awake brain surgery, fluorescent-guided resection with 5-aminolevulinic acid, and intraoperative imaging techniques such as ultrasound or MRI [ 36 ]. In case of eloquent located tumors, complete resection without causing a new permanent neurological deficit is not always feasible and residual tumor tissue can be left in situ as risk–benefit analysis [ 22 , 28 , 31 , 37 ].…”