Single-shot bevacizumab for cerebral radiation injury

A Synthetic Steroid 5α-Androst-3β, 5, 6β-triol Alleviates Radiation-Induced Brain Injury in Mice via Inhibiting GBP5/NF-κB/NLRP3 Signal Axis

Radiotherapy for head and neck tumors can lead to a severe complication known as radiation-induced brain injury (RIBI). However, the underlying mechanism of RIBI development remains unclear, and limited prevention and treatment options are available. Neuroactive steroids have shown potential in treating neurological disorders. 5α-Androst-3β, 5, 6β-triol (TRIOL), a synthetic neuroprotective steroid, holds promise as a treatment candidate for RIBI patients. However, the neuroprotective effects and underlying mechanism of TRIOL on RIBI treatment are yet to be elucidated. In the present study, our findings demonstrate TRIOL's potential as a neuroprotective agent against RIBI. In gamma knife irradiation mouse model, TRIOL treatment significantly reduced brain necrosis volume, microglial activation, and neuronal loss. RNA-sequencing, immunofluorescence, real-time quantitative polymerase chain reaction, siRNA transfection, and western blotting techniques revealed that TRIOL effectively decreased microglial activation, proinflammatory cytokine release, neuron loss, and guanylate-binding protein 5 (GBP5) expression, along with its downstream signaling pathways NF-κB and NLRP3 activation in vitro. In summary, TRIOL effectively alleviate RIBI by inhibiting the GBP5/NF-κB/NLRP3 signal axis, reducing microglia activation and pro-inflammation cytokines release, rescuing neuron loss. This study highlights the potential of TRIOL as a novel and promising therapy drug for RIBI treatment.

The incidence and predictive factors of secondary epilepsy in patients with supratentorial brain metastases (st-BMs) after stereotactic radiosurgery: A multicenter retrospective study

OBJECTIVE

To evaluate the incidence and the independent risk factors of SRS-related epilepsy in patients with supratentorial brain metastases (st-BMs), providing evidences for prevention or reduction secondary epilepsy after SRS.

METHODS

Patients with st-BMs from four gamma knife centers who developed secondary epilepsy after SRS were retrospectively studied between January 1, 2017 and June 31, 2023. The incidence and clinical characteristics of the patients with secondary epilepsy were analyzed. The predictive role of baseline clinical-demographic variables was evaluated according to univariate and multivariate logistic regression model. The impact of secondary epilepsy on patients' OS was evaluated as well by log-rank test.

RESULTS

11.3 % (126/1120) of the patients with totally 158 st-BMs experienced secondary epilepsy after SRS in median 21 days. 61.9 % (78/126) of the patients experienced simple partial seizures. 91.3 % (115/126) patients achieved good seizure control after received 1-2 kinds of AEDs for median 90 days, while 7.1 % (9/126) of the patients suffered from refractory epilepsy. Patients had higher risk of secondary epilepsy if the tumor located in cortex and/or hippocampus, peri-tumor edema larger than 20.3 cm3 before SRS, had epilepsy history, and failed to receive bevacizumab prior to SRS. There was no difference in the OS of patients who experience secondary epilepsy or not after SRS.

CONCLUSIONS

The incidence of SRS-related secondary epilepsy is 11.3 % in patients with st-BMs in this retrospective study. The risk of secondary epilepsy is higher in patients with st-BM located in cortex and/or hippocampus area, peri-tumor edema larger than 20.3 cm3 before SRS, and epilepsy history. Bevacizumab is suggested prior to SRS therapy, as it could be used for the control of peri-tumor edema and SRS-related damage, hence reduce the risk of secondary epilepsy. However, whether or not patients suffered from secondary epilepsy after SRS does not affect their OS.

Bevacizumab reduces peritumoral brain edema in lung cancer brain metastases after radiotherapy

BACKGROUND

The aim of this study was to investigate the efficacy of bevacizumab (Bev) in reducing peritumoral brain edema (PTBE) after stereotactic radiotherapy (SRT) for lung cancer brain metastases.

METHODS

A retrospective analysis was conducted on 44 patients with lung cancer brain metastases (70 lesions) who were admitted to our oncology and Gamma Knife center from January 2020 to May 2022. All patients received intracranial SRT and had PTBE. Based on treatment with Bev, patients were categorized as SRT + Bev and SRT groups. Follow-up head magnetic resonance imaging was performed to calculate PTBE and tumor volume changes. The edema index (EI) was used to assess the severity of PTBE. Additionally, the extent of tumor reduction and intracranial progression-free survival (PFS) were compared between the two groups.

RESULTS

The SRT + Bev group showed a statistically significant difference in EI values before and after radiotherapy (p = 0.0115), with lower values observed after treatment, but there was no difference in the SRT group (p = 0.4008). There was a difference in the distribution of EI grades in the SRT + Bev group (p = 0.0186), with an increased proportion of patients at grades 1-2 after radiotherapy, while there was no difference in the SRT group (p > 0.9999). Both groups demonstrated a significant reduction in tumor volume after radiotherapy (p < 0.05), but there was no difference in tumor volume changes between the two groups (p = 0.4089). There was no difference in intracranial PFS between the two groups (p = 0.1541).

CONCLUSION

Bevacizumab significantly reduces the severity of PTBE after radiotherapy for lung cancer. However, its impact on tumor volume reduction and intracranial PFS does not reach statistical significance.

Immune Checkpoint Inhibitor-Induced Cerebral Pseudoprogression: Patterns and Categorization

Background

The inclusion of immune checkpoint inhibitors (ICIs) in therapeutic algorithms has led to significant survival benefits in patients with various metastatic cancers. Concurrently, an increasing number of neurological immune related adverse events (IRAE) has been observed. In this retrospective analysis, we examine the ICI-induced incidence of cerebral pseudoprogression and propose a classification system.

Methods

We screened our hospital information system to identify patients with any in-house ICI treatment for any tumor disease during the years 2007-2019. All patients with cerebral MR imaging (cMRI) of sufficient diagnostic quality were included. cMRIs were retrospectively analyzed according to immunotherapy response assessment for neuro-oncology (iRANO) criteria.

Results

We identified 12 cases of cerebral pseudoprogression in 123 patients treated with ICIs and sufficient MRI. These patients were receiving ICI therapy for lung cancer (n=5), malignant melanoma (n=4), glioblastoma (n=1), hepatocellular carcinoma (n=1) or lymphoma (n=1) when cerebral pseudoprogression was detected. Median time from the start of ICI treatment to pseudoprogression was 5 months. All but one patient developed neurological symptoms. Three different patterns of cerebral pseudoprogression could be distinguished: new or increasing contrast-enhancing lesions, new or increasing T2 predominant lesions and cerebral vasculitis type pattern.

Conclusion

Cerebral pseudoprogression followed three distinct patterns and was detectable in 3.2% of all patients during ICI treatment and in 9.75% of the patients with sufficient brain imaging follow up. The fact that all but one of the affected patients developed neurological symptoms, which would be classified as progressive disease according to iRANO criteria, mandates vigilance in the diagnosis and treatment of ICI-induced cerebral lesions.

Radiotherapy of High-Grade Gliomas: First Half of 2021 Update with Special Reference to Radiosensitization Studies

Albeit the effort to develop targeted therapies for patients with high-grade gliomas (WHO grades III and IV) is evidenced by hundreds of current clinical trials, radiation remains one of the few effective therapeutic options for them. This review article analyzes the updates on the topic "radiotherapy of high-grade gliomas" during the period 1 January 2021-30 June 2021. The high number of articles retrieved in PubMed using the search terms ("gliom* and radio*") and manually selected for relevance indicates the feverish research currently ongoing on the subject. During the last semester, significant advances were provided in both the preclinical and clinical settings concerning the diagnosis and prognosis of high-grade gliomas, their radioresistance, and the inevitable side effects of their treatment with radiation. The novel information concerning tumor radiosensitization was of special interest in terms of therapeutic perspective and was discussed in detail.