title: [Controversy in the management of WHO grade II gliomas in eloquent brain areas: recent literature review].
abstract: Recent studies have shown that diffuse grade II gliomas (GGII) located in eloquent brain areas represent over 80% of all GGII. The optimal management of these tumours is still controversial. It has long been considered that surgery is not an option for GGII within eloquent areas, due to the high risk of inducing postoperative sequelae in patients with normal neurological explorations. However, the safety of these surgeries has significantly improved in recent years due to the rapid development of techniques enabling a precise mapping of brain functions. Noninvasive functional neuroimaging techniques have been recently developed, enabling cortical mapping of the entire brain prior to surgical procedures. Such precise data provide a preoperative estimation of the location of eloquent areas in relation to the tumour, which is essential for surgical planning and preoperative assessment of morbidity for various surgical approaches. The intraoperative electrical stimulation (IES) mapping technique consists in the application of a bipolar electrode on the brain tissue, enabling an accurate location of brain functions. This provides unique assistance in GGII resection, as it generates a discrete and transient "virtual" lesion within the eloquent tissue. Tumour removal is then tailored according to functional boundaries in order to optimise the quality of resection and to minimise the risk of postoperative sequelae, preserving quality of life. For patients with a GGII in an eloquent area, the possibility of an early resection should be evaluated by a multidisciplinary neuro-oncology team specialising in the management of such tumours.
authors.affiliation: Departamento de Neurocirugía, Hospital Universitario Marqués de Valdecilla e Instituto de Formación e Investigación Marqués de Valdecilla (IFIMAV), Santander, Cantabria, España.
authors.forename: Juan
authors.initials: J
authors.lastname: Martino
authors.forename: Elsa
authors.initials: E
authors.lastname: Gómez
authors.forename: Enrique
authors.initials: E
authors.lastname: Marco de Lucas
authors.forename: Marian
authors.initials: M
authors.lastname: Martínez
authors.forename: Roberto
authors.initials: R
authors.lastname: Ocon
authors.forename: José Manuel
authors.initials: JM
authors.lastname: Valle-Folgueral
authors.forename: Marco
authors.initials: M
authors.lastname: Vega
authors.forename: Alfonso
authors.initials: A
authors.lastname: Vázquez-Barquero
mesh_terms: D001921:Brain; D001931:Brain Mapping; D001932:Brain Neoplasms; D005910:Glioma; D006801:Humans; D011788:Quality of Life