Standard Dose Versus Reduced Dose Single Fraction Preoperative Radiosurgery for Resected Brain Metastases (PROPS-BM)...

Area of Science:

• Neurosurgery
• Radiation Oncology
• Oncology

Background:

• Single fraction preoperative stereotactic radiosurgery (SRS) for brain metastases often involves dose reduction.
• The impact of this dose reduction on outcomes and toxicity is not well understood.

Purpose of the Study:

• To compare outcomes and toxicity between standard dose (SD) and reduced dose (RD) single fraction preoperative SRS.
• To evaluate the efficacy and safety of different SRS dosing strategies before surgical resection of brain metastases.

Main Methods:

• Retrospective and prospective data from the PROPS-BM international multicenter registry.
• Inclusion of patients with brain metastases from solid cancers treated with single fraction preoperative SRS and planned resection.
• Comparison of outcomes (cavity local recurrence, adverse radiation effects, meningeal disease, overall survival) between SD and RD cohorts using multivariable and propensity score matched analyses.

Main Results:

• No significant difference in 2-year cavity local recurrence (16% vs 15%), adverse radiation effects (8% vs 6%), or overall survival (49% vs 36%) between SD and RD.
• Cavity local recurrence risk increased with larger lesion size, irrespective of SRS dose.
• Results remained consistent across lesion size subgroups and in propensity score matched cohorts.

Conclusions:

• Both standard dose and reduced dose single fraction preoperative SRS achieve excellent local control and acceptable toxicity.
• Reduced dose SRS does not appear to offer superior efficacy or safety compared to standard dose SRS.
• Further research is needed to optimize SRS dose and fractionation for preoperative treatment of brain metastases.