Very Large Metastases to the Brain: Retrospective Study on Outcomes of Surgical Management

Surgical resection versus stereotactic radiosurgery for the treatment of brain metastases in the motor cortex; a meta-analysis and systematic review

Brain metastasis in the motor cortex is a challenging condition to treat. Surgical resection or stereotactic radiosurgery (SRS)/hypofractionated stereotactic radiotherapy (hypoSRT) are valuable options up to now. Due to its unique location and potential for neurologic deficits, neither treatment is entirely satisfactory. There is still a lack of data on the treatment result of motor cortex metastasis. This study provides a comprehensive review and meta-analysis comparing surgery and SRS/hypoSRT for treating brain metastasis in the motor cortex. Core databases, including PubMed, Embase, and the Cochrane Library, were systematically searched for brain metastasis in the motor cortex, demonstrating the clinical outcomes of both surgery and SRS/hypoSRT. Motor power outcome and treatment-associated complication rates were thoroughly evaluated. Twenty-five articles were listed for full-text review. Among them, 13 articles were eligible for inclusion criteria: retrospective cohort studies comparing surgery and SRS/hypoSRT. There are 323 patients in the surgery group and 220 in the SRS/hypoSRT group. The motor outcome is better in surgery group, but without statistical significance (0.49 vs 0.37, p = 0.3937) and treatment-related complication is lower in surgery group with statistical significance (0.09 vs 0.26, p = 0.0218). Treatment modality should be tailored by the patient's performance status, history of radiation, presence of ongoing chemotherapy, or extracranial progression status.

Limitations of outcome prediction based on interfractional volume changes of large (≥ 10cm3) brain metastases during fractionated gamma knife radiosurgery

PURPOSE

This study investigated the interfractional volume changes of large (≥ 10 cm3) brain metastases (BMs) during fractionated gamma knife radiosurgery (FGKRS) to assess its predictive value for tumor control outcomes.

METHODS

The patients who underwent FGKRS for large BMs between January 2017 and December 2022 in our center were reviewed. The interfractional volume change was defined as the disparity in tumor volume (TV) measured between the magnetic resonance images acquired on the first treatment day and those obtained after 2 or 3 fractions during the course of FGKRS.

RESULTS

A total of 73 lesions in 70 patients with various primary pathologies were included. Over a median follow-up period of 11 months (range 1-77), the tumor control rate was 63%. Initial TV (cm3) was associated with progression free survival (PFS) and overall survival (OS) in both univariate and multivariate analyses (p = 0.01). Interfractional TV changes revealed an increase in 13 (17.8%) lesions, no change in 14 (19.2%) lesions, and a decrease in 46 (63.0%) lesions, with a mean volume reduction of 5% ± 0.12. Three cut-offs (5%, 10% and 15% volume decrement) were established and patients were divided into two groups based on each reference point. However, there were no significant differences in PFS and OS between the two groups, irrespective of the chosen cut-off value used.

CONCLUSION

Interfractional volume changes of large BMs were not found to be associated with tumor control outcomes. Neither significant interfractional volume reduction nor significant volume increase necessarily predicts the tumor control, making early close monitoring essential after FGKRS.

Management Paradigm of Central Nervous System Metastases in NSCLC: An Australian Perspective

Life-prolonging central nervous system active systemic therapies for metastatic NSCLC have increased the complexity of managing brain metastases (BMs). Australian medical oncologists, radiation oncologists, and neurosurgeons discussed the evidence guiding the diverse clinical approaches to the management of BM in NSCLC. The Australian context is broadly applicable to other jurisdictions; therefore, we have documented these discussions as principles with broader applications. Patient management was stratified according to clinical and radiologic factors under two broad classifications of newly diagnosed BMs: symptomatic and asymptomatic. Other important considerations include the number and location of metastases, tumor histotypes, molecular subtype, and treatment purpose. Careful consideration of the pace and burden of symptoms, risk of worsening neurologic function at a short interval, and extracranial disease burden should determine whether central nervous system active systemic therapies are used alone or in combination with local therapies (surgery with or without radiation therapy). Most clinical trial evidence currently focuses on historical treatment options or a single treatment modality rather than the optimal sequencing of multiple modern therapies; therefore, an individualized approach is key in a rapidly changing therapeutic landscape.

Radiation Therapy for Brain Metastases: An ASTRO Clinical Practice Guideline

PURPOSE

This guideline provides updated evidence-based recommendations addressing recent developments in the management of patients with brain metastases, including advanced radiation therapy techniques such as stereotactic radiosurgery (SRS) and hippocampal avoidance whole brain radiation therapy and the emergence of systemic therapies with central nervous system activity.

METHODS

The American Society for Radiation Oncology convened a task force to address 4 key questions focused on the radiotherapeutic management of intact and resected brain metastases from nonhematologic solid tumors. The guideline is based on a systematic review provided by the Agency for Healthcare Research and Quality. Recommendations were created using a predefined consensus-building methodology and system for grading evidence quality and recommendation strength.

RESULTS

Strong recommendations are made for SRS for patients with limited brain metastases and Eastern Cooperative Oncology Group performance status 0 to 2. Multidisciplinary discussion with neurosurgery is conditionally recommended to consider surgical resection for all tumors causing mass effect and/or that are greater than 4 cm. For patients with symptomatic brain metastases, upfront local therapy is strongly recommended. For patients with asymptomatic brain metastases eligible for central nervous system-active systemic therapy, multidisciplinary and patient-centered decision-making to determine whether local therapy may be safely deferred is conditionally recommended. For patients with resected brain metastases, SRS is strongly recommended to improve local control. For patients with favorable prognosis and brain metastases receiving whole brain radiation therapy, hippocampal avoidance and memantine are strongly recommended. For patients with poor prognosis, early introduction of palliative care for symptom management and caregiver support are strongly recommended.

CONCLUSIONS

The task force has proposed recommendations to inform best clinical practices on the use of radiation therapy for brain metastases with strong emphasis on multidisciplinary care.