Modern surgical management of incidental gliomas

Abstract

Purpose Gliomas are the most common primary tumors of the central nervous system and are categorized by the World Health Organization into either low-grade (grades 1 and 2) or high-grade (grades 3 and 4) gliomas. A subset of patients with glioma may experience no tumor-related symptoms and be incidentally diagnosed. These incidental low-grade gliomas (iLGG) maintain controversial treatment course despite scientific advancements. Here we highlight the recent advancements in classification, neuroimaging, and surgical management of these tumors. Methods A review of the literature was performed. The authors created five subtopics of focus: histological criteria, diagnostic imaging, surgical advancements, correlation of surgical resection and survival outcomes, and clinical implications. Conclusions Alternating studies suggest that these tumors may experience higher mutational rates than their counterparts. Significant progress in management of gliomas, regardless of the grade, has been made through modern neurosurgical treatment modalities, diagnostic neuroimaging, and a better understanding of the genetic composition of these tumors. An optimal treatment approach for patients with newly diagnosed iLGG remains ill-defined despite multiple studies arguing in favor of safe maximal resection. Our review emphasizes the not so benign nature of incidental low grade glioma and further supports the need for future studies to evaluate survival outcomes following surgical resection.

Supratotal Surgical Resection for Low-Grade Glioma: A Systematic Review

“…Four of the studies focused exclusively on asymptomatic or "incidental" LGGs, which represent only a small total of the overall LGG population. These two groups of LGGs are considered distinct by the neurosurgical literature, as incidental gliomas remain controversial in terms of treatment planning, though current practice has evolved such that early surgery is currently favored [5,30,31]. Our regrouping of SupTR patients based on preoperative symptomatology did not demonstrate wide differences in the percentage of patients receiving SupTR, permanent neurological deficits, or OS.…”

“…The primary argument for supratotal resection of LGG is that a more aggressive resection can achieve a greater margin of resection, reducing the risk of malignant transformation and improving clinical outcomes [13,21,[27][28][29]. However, supratotal resection may increase risks of neurologic complications relative to gross total resection through the removal of potentially functional brain around the tumor [13,22,23,30]. Thus, the clinical impact of supratotal surgical resection remains controversial.…”

Combination of MRI-based prediction and CRISPR/Cas12a-based detection for IDH genotyping in glioma

“…One aspect that has garnered recent attention is the management of low-grade gliomas that are incidentally detected without objective clinical signs during MRI screening for unrelated syndromes. Emerging evidence emphasizes the importance of pursuing early interventions to achieve maximal recovery, potentially prolonging survival and delaying malignant progression in small “incident” gliomas 43 , 44 . However, we could not accurately conclude whether this MRI model has good accuracy for smaller “sporadic” gliomas, as all the enrolled patients had obvious clinical signs.…”