Is awake surgery for supratentorial adult low-grade gliomas the gold standard?

Is "En Masse" Tumor Resection a Safe Surgical Strategy for Low-Grade Gliomas? Feasibility Report on 74 Patients Treated Over Four Years

Background

Gliomas are "confined" tumors arising from a named white fiber tract and displacing adjoining "normal" white fibers. The surgical strategy of "en masse" resection of gliomas based on this concept is evaluated.

Objective

We evaluate the feasibility of the surgical strategy of "en masse" tumor resection for low-grade gliomas arising from the short arcuate fibers.

Methods

We retrospectively evaluated our series of 74 patients with low-grade gliomas involving the short arcuate fibers who were operated on between the years January 2016 and June 2019. The tumor resection was done on the premise that gliomas arise from and grew along a specific white fiber tract and the expanding tumor displaced but did not transgress the border formed by adjoining tracts. Although modified as per the situation, an en masse tumor resection strategy was the basis of surgical resection. Intraoperative motor cortical and subcortical mapping was performed in 14 cases. Awake surgery was performed on 11 patients.

Results

There were 46 males and 28 females. Total/supratotal tumor resection was achieved in 62 (83.8%) patients. Forty-seven patients had an essentially en masse tumor resection. Seventy-one patients improved in their preoperative complaints. The follow-up ranged from 11 to 56 months. Sixty-two patients who underwent a total or supratotal resection were not given any adjuvant treatment. Twelve patients with subtotal resection were subjected to adjuvant radiotherapy with or without additional chemotherapy.

Conclusions

En masse tumor resection of low-grade gliomas is possible and "safe" based on understanding that gliomas are "confined" tumors and have a well-defined plane of surgical dissection.

T2 Fluid-Attenuated Inversion Recovery Resection for Glioblastoma Involving Eloquent Brain Areas Facilitated Through Awake Craniotomy and Clinical Outcome

BACKGROUND

Despite evidence that a greater extent of resection (EOR) improves survival, the role of extended resection based on magnetic resonance imaging (MRI) fluid-attenuated inversion recovery (FLAIR) in the prognosis of glioblastoma (GBM) remains controversial. This study aims to investigate the role of additional resection of FLAIR-detected abnormalities and its influence on clinical outcomes of patients with GBM.

METHODS

Forty-six patients with newly diagnosed GBM involving eloquent brain areas were included. Surgeries were performed using awake craniotomy (AC) or AC combined with sodium fluorescein (SF) guidance. Following total removal of the contrast-enhancing tumor area, the EOR of FLAIR abnormalities was dichotomized to identify the best separation threshold for progression-free survival (PFS), overall survival (OS), and 30-day postoperative neurologic function of patients with GBM.

RESULTS

The threshold for removal of FLAIR abnormalities affecting survival was determined to be 25%. The median OS and PFS were shorter in the group with FLAIR resection <25% compared with the group with FLAIR resection ≥25% (12 months vs. 26 months; P = 0.001 and 6 months vs. 15 months; P = 0.016, respectively). Univariate and multivariate analyses identified tumor location within or near the eloquent brain areas and the 25% threshold for FLAIR EOR as independent factors affecting OS and PFS.

CONCLUSIONS

Identifying a feasible threshold for the resection of FLAIR abnormalities is valuable in improving the survival of patients with GBM. Extended resection of GBM involving eloquent brain areas was safe when using a combination of AC and SF-guided surgery.