Safety and outcomes of resection of butterfly glioblastoma

Abstract

<jats:sec><jats:title>OBJECTIVE</jats:title><jats:p>Butterfly glioblastoma (bGBM) is a rare type of GBM, characterized by a butterfly pattern on MRI studies because of its bihemispheric involvement and invasion of the corpus callosum (CC). There is a profound gap in the knowledge regarding the optimal treatment approach as well as the safety and survival benefits of resection in treating this aggressive brain tumor. In this retrospective study, authors add to our understanding of these tumors by identifying the clinical characteristics and outcomes of patients with bGBM.</jats:p></jats:sec><jats:sec><jats:title>METHODS</jats:title><jats:p>An institutional database was reviewed for GBM cases treated in the period from 2004 to 2014. Records were reviewed to identify adult patients with bGBM. Cases of GBM with invasion of the CC without involvement of the contralateral hemisphere and bilateral GBMs without involvement of the CC were excluded from the study. Patient and tumor characteristics were gleaned from the medical records, and volumetric analysis was performed using T1-weighted MRI studies.</jats:p></jats:sec><jats:sec><jats:title>RESULTS</jats:title><jats:p>From among 1746 cases of GBM, 39 cases of bGBM were identified. Patients had a mean age of 57.8 years at diagnosis. Headache and confusion were the most common presenting symptoms (48.7% and 33.3%, respectively). The median overall survival was 3.2 months from diagnosis with an overall 6-month survival rate of 38.1%. Age, Karnofsky Performance Status at diagnosis, preoperative tumor volume, postoperative tumor volume, and extent of resection were found to significantly impact survival in the univariate analysis. On multivariate analysis, preoperative tumor volume and treatment approach of resection versus biopsy were identified as independent prognostic factors regardless of the patient-specific characteristics of age and KPS at diagnosis. Resection and biopsy were performed in 35.9% and 64.1% of patients, respectively. Resection was found to confer a better prognosis than biopsy (HR 0.37, p = 0.009) with a minimum extent of resection of 86% to observe survival benefits (HR 0.054, p = 0.03). The rate of persistent neurological deficits from resection was 7.14%. Patients younger than 70 years had a better prognosis (HR 0.32, p = 0.003). Patients undergoing resection and receiving adjuvant chemoradiation had a better prognosis than patients who lacked one of the three treatment modalities (HR = 0.34, p = 0.015).</jats:p></jats:sec><jats:sec><jats:title>CONCLUSIONS</jats:title><jats:p>Resection of bGBM is associated with low persistent neurological deficits, with improvement in survival compared to biopsy. A more aggressive treatment approach involving aggressive resection and adjuvant chemoradiation has significant survival benefits and improves outcome.</jats:p></jats:sec>

Surgery for IDH1/2 wild-type glioma invading the corpus callosum

“…This observation shows an important limitation of our retrospective study because large tumors were never who was able to show that mass reduction causes favoral neurological outcome and leads to improved functional performance even if the surgical removal comes with higher risk of surgery-associated complications. In line with other authors, we showed a survival benefit for patients who underwent tumor resection [12][13][14]. However, compared to other published works, the extent of survival benefits is distinctly lower in our cohort.…”

“…Therefore, until lately, diagnostic and molecular profiling via tumor biopsy was widely favored over the attempt of gross-total tumor resection. Yet, a growing number of authors have published data highlighting the benefits of resection of glioblastoma of the corpus callosum (ccGBM), specifically regarding improved overall survival without aggravating persistent neurological deficits [12][13][14]. Unfortunately, there is a lack of consistent molecular profiling of the tumors in the previous studies, which leads to a disputable interpretation of the benefits of surgical resection upon survival in this subset of tumors.…”

Benefits of glioma resection in the corpus callosum

“…Percentage of patients impaired per domain, considered as a decrease in a Z-score of more than 1.5 SD, at time points t1 (prior to surgery), t2 (before hospital discharge) and t3 (at long-term follow-up). 10 . Most importantly, patients who underwent biopsy of butterfly glioma experienced significantly shortened OS, ranging from 1.5 to 4.2 months 9,10,12,20 .…”

“…However, median survival of patients with butterfly glioblastoma was markedly improved by tumor resection, doubling a patient's remaining life time in comparison to tumor biopsy only; a resection of ≥ 65% of the tumor volume was found to be associated with longer overall survival. Another analysis on the impact of EoR in butterfly glioblastoma was provided by Dayani et al, and they found out that the amount of total tumor reduction, but not EoR within the corpus callosum influenced patients' overall survival (OS) 10 . Chen et al equally observed EoR to be independently associated with longer OS in both, low-and high-grade glioma, whereas no such association was found for corpus callosum involvement which had no significant impact on OS 11 .…”

“…While these three publications provided evidence that the resection of tumors involving the corpus callosum improves patients' overall survival [9][10][11] , only one publication by Dziurzynski et al reported on the doubtful benefit of the resection of butterfly glioblastomas 12 . However, adjuvant treatment had been administered to barely half of their patients, probably confounding their results.…”