Excellent Outcomes with Radiosurgery for Multiple Brain Metastases in ALK and EGFR Driven Non-Small Cell Lung Cancer

Area of Science:

• Oncology
• Radiation Oncology
• Medical Physics

Background:

• Non-small cell lung cancer (NSCLC) with EGFR mutations or ALK rearrangements has a better prognosis.
• Whole brain radiation therapy (WBRT) for brain metastases (BMs) can cause cognitive decline.
• Minimizing WBRT toxicity is crucial for patients with BMs.

Purpose of the Study:

• To evaluate the efficacy and safety of stereotactic radiosurgery (SRS) for multiple BMs in EGFR-mutated and ALK-rearranged NSCLC.
• To determine if SRS without WBRT is a viable option for patients with four or more BMs.
• To assess long-term outcomes, including survival and freedom from WBRT.

Main Methods:

• Retrospective review of 35 patients with EGFR-mutated or ALK-rearranged NSCLC and at least four BMs treated with SRS between 2008 and 2017.
• Analysis of treatment details, including the number of BMs treated per session and in total.
• Evaluation of survival, freedom from neurologic death, and freedom from WBRT.

Main Results:

• Median survival was 3.0 years (4.2 for ALK, 2.4 for EGFR).
• Survival was similar regardless of the number of BMs treated.
• Low hippocampal and whole-brain radiation doses were achieved, with 5-year freedom from WBRT at 97% and freedom from neurologic death at 84%.

Conclusions:

• SRS without WBRT is a safe and effective treatment for multiple BMs in EGFR-mutated and ALK-rearranged NSCLC.
• This approach supports long-term survival and avoids the neurocognitive toxicities of WBRT.
• SRS is a recommended strategy for patients with four or more BMs in this specific NSCLC population.