Clinical Study of Stereotactic Radiosurgery Combined with Osimertinib in the Treatment of EGFR-Positive Lung Cancer Brain Metastases

Background: To observe the safety and efficacy of stereotactic radiosurgery synchronous osimertinib compared with osimertinib alone in the treatment of patients with brain metastasis of EGFR-positive non-small cell lung cancer. Methods: EGFR-positive non-small cell lung cancer patients with brain metastasis admitted to our hospital from January 2018 to January 2020 were selected. The experimental group: 30 patients were treated with SRS combined with osimertinib. SRS treatment: prescription dose (d = 0 - 40 mm, 27 Gy/3f); targeted treatment scheme: osimertinib, 80 mg/day, taken orally after SRS treatment; control group: 30 patients were treated with osimertinib alone; osimertinib was maintained until disease progression (PD) or adverse reactions were intolerable. PFS, ORR, DCR and AEs of intracranial lesions were observed. Results: This study included 60 patients, with a median age of 54.8 (35 - 79) years, included 41 males and 19 females, with a median follow-up time of 34.5 (30 - 42) months. There were 30 cases in the experimental group and 30 cases in the control group, respectively. The ORR of intracranial lesions in the two groups were 96.67% and 66.67%, respectively, with significant statistical difference between the two groups (p = 0.003). The DCR of intracranial lesions was 100% and 96.67%, respectively, and there was no significant difference between the two groups (p = 0.313). The median PFS of intracranial lesions was 26.5 months and 16.5 months, respectively. There was a significant difference between the two groups (p Conclusions: SRS synchronous osimertinib therapy is more effective than simple osimertinib in the treatment of brain metastasis of EGFR-positive non-small cell lung cancer patients, and the side effects are tolerable. We look forward to further large phase III clinical studies to confirm it.