The Dual Effect of SRS and Immunotherapy for Brain 
Metastases: Balancing Efficacy and Toxicity

Jie Che; Lin Yin*

doi:10.70711/pmr.v3i1.8070

The Dual Effect of SRS and Immunotherapy for Brain Metastases: Balancing Efficacy and Toxicity

Jie Che, Lin Yin*

Abstract

The therapeutic landscape for brain metastases (BMs) has been profoundly reshaped by the concurrent evolution of two powerful
modalities: stereotactic radiosurgery (SRS) and immune checkpoint inhibitors (ICIs). The rational combination of these treatmentswhere
SRS acts as an in situ vaccine to generate tumour-specific immunity and ICIs unleash the ensuing systemic anti-tumour responsepromises to improve intracranial control and overall survival. Mounting clinical evidence, particularly in melanoma and non-small-cell lung
cancer (NSCLC), confirms this potential, with studies demonstrating enhanced survival and even abscopal effects. However, this synergy
constitutes a double-edged sword. The potentiated immune response can also precipitate significant inflammatory toxicities, most notably
an elevated risk of symptomatic radiation necrosis (RN), creating a critical challenge for clinicians. This Review comprehensively synthesizes the current evidence on the efficacy and toxicity of SRSICI therapy. We delve into the ongoing debates regarding optimal treatment
sequencing and dosing, and critically appraise the strategies for diagnosing and managing toxicities. The overarching goal is to provide a
framework for navigating this complex therapeutic paradigm, enabling clinicians to maximize clinical benefit while mitigating the inherent
risks of this potent combination.

Keywords

Stereotactic Radiosurgery; Immunotherapy; Brain Metastases; Dual Effect

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References

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DOI: http://dx.doi.org/10.70711/pmr.v3i1.8070

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