Repeat Resection and Intraoperative Radiotherapy for Malignant Gliomas of the Brain: A History and Review of Current Techniques

Prospective comparative study of intraoperative balloon electronic brachytherapy versus resection with multidisciplinary adjuvant therapy for recurrent glioblastoma

Background

Intraoperative balloon electronic brachytherapy (IBEB) may provide potential benefit for local control of recurrent cerebral glioblastomas (GBMs).

Methods

This is a preliminary report of an open-label, prospective, comparative cohort study conducted in two neurosurgical centers with ongoing follow-up. At recurrence, patients at one center (n = 15) underwent reresection with IBEB while, at the second center (n = 15), control subjects underwent re-resection with various accepted second-line adjuvant chemoradiotherapy options. A comparative analysis of overall survival (OS) and local progression-free survival (LPFS) following re-resection was performed. Exploratory subgroup analysis based on postoperative residual contrast-enhanced volume status was also done.

Results

In the IBEB group, median LPFS after re-resection was significantly longer than in the control group (8.0 vs. 6.0 months; log rank χ² = 4.93, P = 0.026, P < 0.05). In addition, the median OS after second resection in the IBEB group was also significantly longer than in the control group (11.0 vs. 8.0 months; log rank χ² = 4.23, P = 0.04, P < 0.05).

Conclusion

These hypothesis-generating results from a small cohort of subjects suggest putative clinical benefit in OS and LPFS associated with maximal safe re-resection of recurrent GBM with IBEB versus re-resection and standard adjuvant therapy, a hypothesis that deserves further testing in an appropriately powered clinical trial.

Re-irradiation for high-grade gliomas: Has anything changed?

Optimal management after recurrence or progression of high-grade gliomas is still undefined and remains a challenge for neuro-oncology multidisciplinary teams. Improved radiation therapy techniques, new imaging methods, published experience, and a better radiobiological knowledge of brain tissue have positioned re-irradiation (re-RT) as an option for many of these patients. Decisions must be individualized, taking into account the pattern of relapse, previous treatment, and functional status, as well as the patient’s preferences and expected quality of life. Many questions remain unanswered with respect to re-RT: Who is the most appropriate candidate, which dose and fractionation are most effective, how to define the target volume, which imaging technique is best for planning, and what is the optimal timing? This review will focus on describing the most relevant studies that include re-RT as salvage therapy, with the aim of simplifying decision-making and designing the best available therapeutic strategy.

Recurrent high-grade glioma surgery: a multimodal intraoperative protocol to safely increase extent of tumor resection and analysis of its impact on patient outcome

OBJECTIVE

No consensus exists on the best treatment for recurrent high-grade glioma (HGG), particularly in terms of surgical indications, and scant data are available on the integrated use of multiple technologies to overcome intraoperative limits and pitfalls related to artifacts secondary to previous surgery and radiotherapy. Here, the authors report on their experience with the integration of multiple intraoperative tools in recurrent HGG surgery, analyzing their pros and cons as well as their effectiveness in increasing the extent of tumor resection. In addition, they present a review of the relevant literature on this topic.

METHODS

The authors reviewed all cases in which recurrent HGG had been histologically diagnosed after a first surgery and the patient had undergone a second surgery involving neuronavigation with MRI, intraoperative CT (iCT), 11C-methionine-positron emission tomography (11C-MET-PET), 5-aminolevulinic acid (5-ALA) fluorescence, intraoperative neurophysiological monitoring (IONM), and intraoperative navigated ultrasound (iUS). All cases were classified according to tumor functional grade (1, noneloquent area; 2, near an eloquent area; 3, eloquent area).

RESULTS

Twenty patients with recurrent HGG were operated on using a multimodal protocol. The recurrent tumor functional grade was 1 in 4 patients, 2 in 8 patients, and 3 in the remaining 8 patients. In all patients but 2, 100% EOTR was obtained. Intraoperative 5-ALA fluorescence and navigated iUS showed low specificity and sensitivity. iCT detected tumor remnants in 3 cases. Postoperatively, 6 patients (30%) had worsening neurological conditions: 4 recovered within 90 days, 1 partially recovered, and 1 experienced a permanent deficit. The median Karnofsky Performance Status remained substantially unchanged over the follow-up period. The mean progression-free survival after the second surgery was 7.7 months (range 2-11 months). The mean overall survival was 25.4 months (range 10-52 months), excluding 2 long survivors. Two patients died within 60 days after surgery, and 3 patients were still under follow-up at the end of this study.

CONCLUSIONS

This is the first study reporting the integration of neuronavigation, 5-ALA fluorescence, iUS, iCT, 11C-MET-PET, and IOM during microsurgical resection of recurrent glioma. The authors believe that the proposed multimodal protocol is useful to increase the safety, effectiveness, and EOTR in patients with recurrent HGG and brain alterations secondary to radio- and chemotherapy.

FAM225B Is a Prognostic lncRNA for Patients with Recurrent Glioblastoma

Objective

The overall survival of patients with recurrent glioblastoma (rGBM) is quite different, so clinical outcome prediction is necessary to guide personalized clinical treatment for patients with rGBM. The expression level of lncRNA FAM225B was analyzed to determine its prognostic value in rGBMs.

Methods

We collected 109 samples of Chinese Glioma Genome Atlas (CGGA) RNA sequencing dataset and divided into training set and validation set. Then, we analyzed the expression of FAM225B, clinical characteristics, and overall survival (OS) information. Kaplan-Meier survival analysis was used to estimate the OS distributions. The prognostic value of FAM225B in rGBMs was tested by univariate and multivariate Cox regression analyses. Moreover, we analyzed the biological processes and signaling pathways of FAM225B.

Results

We found that FAM225B was upregulated in rGBMs (P = 0.0009). The expression of FAM225B increased with the grades of gliomas (P < 0.0001). The OS of rGBMs in the low-expression group was significantly longer than that in the high-expression group (P = 0.0041). Similar result was found in the training set (P = 0.0340) and verified in the validation set (P = 0.0292). In multivariate Cox regression analysis, FAM225B was identified to be an independent prognostic factor for rGBMs (P = 0.003). Biological process and KEGG pathway analyses implied FAM225B mainly played a functional role on transcription, regulation of transcription, cell migration, focal adhesion, etc.

Conclusions

FAM225B is expected to be as a new prognostic biomarker for the identification of rGBM patients with poor outcome. And our study provided a potential therapeutic target for rGBMs.