Operative Techniques for Gliomas and the Value of Extent of Resection

Abstract

Summary:Refinement of neurosurgical technique has enabled safer operations with more aggressive outcomes. One cornerstone of modern-day practice is the utilization of intraoperative stimulation mapping. In addition to identifying critical motor pathways, this technique can be adapted to reliably identify language pathways. Given the individual variability of cortical language localization, such awake language mapping is essential to minimize language deficits following tumor resection. Our experience suggests that cortical language mapping is a safe and efficient adjunct to optimize tumor resection while preserving essential language sites, even in the setting of negative mapping data. However, the value of maximizing glioma resections remains surprisingly unclear, as there is no general consensus in the literature regarding the efficacy of extent of glioma resection in improving patient outcome. While the importance of resection in obtaining tissue diagnosis and alleviating symptoms is clear, a lack of Class I evidence prevents similar certainty in assessing the influence of extent of resection. Beyond an analysis of modern intraoperative mapping techniques, we examine every major clinical publication since 1990 on the role of extent of resection in glioma outcome. The mounting evidence suggests that, despite persistent limitations in the quality of available studies, a more extensive surgical resection is associated with longer life expectancy for both low-grade and high-grade gliomas.

Extended Adjuvant Temozolomide with cis-Retinoic Acid for Adult Glioblastoma

“…The extent of surgical resection was not a statistically significant predictor of survival, and yet there was a very strong trend in favor of resection compared with biopsy (p = 0.06). That finding is consistent with the existing literature on surgical resection for adult glioma, although no randomized data are available to support a causal effect [27][28][29][30] . It remains possible that some of the effect is a result of very poor survival in patients in whom surgical resection was not possible.…”

High-grade glial tumors, survival & prognostic factors; 5-year experience from Ankara Oncology Hospital

“…[13,14] Ekstensif rezeksiyonun prognozla ilişkili olduğuna dair sayısız data olmasına rağmen, sağkalımı artırdığına ait birinci sınıf kanıt yoktur. [4,13] Cerrahi, semptomlu ve nörolojik fayda, net patolojik tanı ve moleküler analiz için gerekli dokunun elde edilmesi açısından şarttır.…”

“…[13,14] Ekstensif rezeksiyonun prognozla ilişkili olduğuna dair sayısız data olmasına rağmen, sağkalımı artırdığına ait birinci sınıf kanıt yoktur. [4,13] Cerrahi, semptomlu ve nörolojik fayda, net patolojik tanı ve moleküler analiz için gerekli dokunun elde edilmesi açısından şarttır. [4] Hasta grubumuzda artmış rezeksiyonun sağkalıma faydası olduğu gözlenmiş; bir, üç, beş yıllık genel sağkalım sırasıyla total eksizyon ile %55, %19.9, %9.9 subtotal eksizyon ile %40.8, %14, %14 yanlızca biyopsi ile %16, %0, %0 olarak bulunmuştur (p<0.001).…”

Multimodal Approach to the Surgical Removal of Gliomas in Eloquent Brain Regions

“…Undoubtedly, CSES has gained a prominent role in neurosurgery above all because a large number of studies worldwide have shown a clear advantage in terms of usefulness, safety, and neurological and oncological outcomes (Berger 1994;Duffau et al 2005;Duffau 2006;Kim et al 2009;Sanai & Berger 2009;De Benedictis et al 2010;Spena et al 2010). The spatial accuracy and the ability to perform functional resection (that is, a resection in which limits are represented by spared functions) have met the approval of many neurosurgeons, who now use CSES routinely.…”

“…The ability to maximize resection while preserving a satisfying functional outcome is of particular interest in brain gliomas for two reasons: first, gliomas mostly affect young adults in full social and working activity, so functional outcome is of the utmost relevance. Second, many different studies (Berger 1994;Keles et al 2001;Sanai & Berger 2009;Stendel 2009) have by now demonstrated that total or subtotal resection has a clear impact on survival and, for LGG (low grade glioma), on malignant transformation, and that the extent of resection is strongly affected by eloquence of the tumor location (Chang et al 2008). In some cases, CSES can also guide in the detection of the safest route for removing purely subcortical tumors.…”