Repeated Awake Surgical Resection(s) for Recurrent Diffuse Low-Grade Gliomas: Why, When, and How to Reoperate?

Abstract

Early maximal surgical resection is the first treatment in diffuse low-grade glioma (DLGG), because the reduction of tumor volume delays malignant transformation and extends survival. Awake surgery with intraoperative mapping and behavioral monitoring enables to preserve quality of life (QoL). However, because of the infiltrative nature of DLGG, relapse is unavoidable, even after (supra)total resection. Therefore, besides chemotherapy and radiotherapy, the question of reoperation(s) is increasingly raised, especially because patients with DLGG usually enjoy a normal life with long-lasting projects. Here, the purpose is to review the literature in the emerging field of iterative surgeries in DLGG. First, long-term follow-up results showed that patients with DLGG who underwent multiple surgeries had an increased survival (above 17 years) with preservation of QoL. Second, the criteria guiding the decision to reoperate and defining the optimal timing are discussed, mainly based on the dynamic intercommunication between the glioma relapse (including its kinetics and pattern of regrowth) and the reactional cerebral reorganization—i.e., mechanisms underpinning reconfiguration within and across neural networks to enable functional compensation. Third, how to adapt medico-surgical strategy to this individual spatiotemporal brain tumor interplay is detailed, by considering the perpetual changes in connectome. These data support early reoperation in recurrent DLGG, before the onset of symptoms and before malignant transformation. Repeat awake resection(s) should be integrated in a global management including (neo)adjuvant medical treatments, to enhance long-lasting functional and oncological outcomes. The prediction of potential and limitation of neuroplasticity at each step of the disease must be improved to anticipate personalized multistage therapeutic attitudes.

Awake brain mapping by direct cortical stimulation; technical note to get higher resection rate and low morbidity in low-grade glioma patients

“…Such data support the rising use of an intrasurgical approach of functional mapping in recent years as well as the validity of awake mapping to maintain the quality of life of patients who have undergone surgery for a low-grade glioma. The long-term quality of life of patients with adult low-grade gliomas improved as a result of the identification of the functional region 17 , 18 .…”

Nuancing the Limitations of Axonal Plasticity in World Health Organization Grade II Gliomas: White Matter Tracts Compensation Is Driven by Cortical Remodeling

“…[30][31][32][33] These compensatory mechanisms were facilitated by postsurgical rehabilitation, 34 possibly leading to reoperation(s) with optimization of the extent of resection (EOR) while avoiding deficit. 35 Despite some degrees of neuroplasticity of WM networks, 36 such processes are less effective at the axonal level, both in physiologyexplaining few interindividual variations regarding the functional anatomy of the WM tracts-and in brain-damaged patients, including with GIIG. 14 Indeed, accurate neuropsychological assessments performed at diagnosis in patients with GIIG detected troubles in more than 50% of cases, 24 correlated with the invasion of WM tracts.…”