Updated perspectives on awake neurosurgery with cognitive and emotional assessment for patients with low-grade gliomas

ABSTRACT

Introduction: Thanks to early extensive surgical resection combined with medical oncological therapies, life expectancy dramatically increased in low-grade glioma (LGG), with an overall survival currently over 15 years. Therefore, patients should be able to maintain valuable family and socio-professional activities.

Areas covered: For many decades, cognitive and emotional aspects were neglected by surgical and medical neurooncologists. The goal of surgery was to avoid hemiplegia and/or aphasia, with no considerations regarding behavior. However, because LGG patients live longer, they must be cognitively and affectively able to make long-term projects. Preservation of higher-order functions should be considered systematically in LGG surgery by means of awake cognitive/emotional mapping and monitoring.

Expert opinion: The aim is to incorporate recent advances in neurosciences, which proposed revisited models of cerebral processing relying on a meta-network perspective, into the pre-, intra- and postoperative procedure. In this connectomal approach, brain functions result from complex interactions within and between neural networks. This improved understanding of a constant instability of the neural system allows a better cognitive/emotional assessment before and after each treatment over years, in order to preserve personality and adaptive behavior for each LGG patient, based on his/her own definition of quality of life. It is time to create oncological neurosciences.

KEYWORDS:

• Awake mapping
• brain connectome
• cognition
• direct electrical stimulation
• glioma
• neuroplasticity
• quality of life
• surgery
• survival

Article highlights

• Due to a longer life expectancy in LGG patients (≥15 years), especially thanks to maximal surgical resection, preservation of a perfect quality of life (QoL) should be a priority

• Neurocognitive, emotional, psychological and behavioral status must be evaluated in a systematic and rigorous way, including by taking account of the personality of each patient

• To this end, subjective complaints and objective comprehensive neuropsychological scores should be collected at the time of diagnosis, as well as before and after each treatment

• Intrasurgical stimulation mapping with on-line neurocognitive and emotional monitoring in awake patient has to be considered in all cases, regardless of the tumor location

• A connectome-based surgery achieved up to cortical hubs and subcortical white matter tracts critical for brain functions improves both extent of resection and QoL

• A better knowledge of brain processing is crucial, based on dynamic interplay within and across neural circuits, in a meta-network perspective breaking with localizationism

• Interactions between glioma cells and neurons are critical to understand complex relationships underlying tumor progression and reactional neuroplastic phenomena

• Individualized multistep therapeutic management should be adapted to each patient over years, with the ultimate goal of giving them the opportunity to make long-term projects regarding familial, social and professional aspects

Declaration of interest

The author has no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.