Optimal Sequence of Local and EGFR-TKI Therapy for EGFR-Mutant Non-Small Cell Lung Cancer With Brain Metastases Stratified by Number of Brain Metastases

Abstract

It is unclear whether local therapy (LT) or epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) should take precedence for patients with EGFR-mutant non-small cell lung cancer (NSCLC) and brain metastases (BMs). The number of BMs is important in the choice of LT, including whole-brain radiation therapy, stereotactic radiosurgery, and surgery. We retrospectively evaluated cases of EGFR-mutant non-small cell lung cancer with BMs from a single site. Patients were divided into 2 groups based on upfront therapy-EGFR-TKI (TKI) or LTs-and subsequently stratified by the number of BMs. Among 176 patients, 61% received upfront EGFR-TKI, and 39% received upfront LT. The number of patients with 1 to 4 BMs was similar (56% vs 52%; P=.61). All patients with 1 to 4 BMs in the LT group, except for surgical cases, received stereotactic radiosurgery (n=31). Among those with ≥5 BMs, most (n=27; 82%) received whole-brain radiation therapy. There was no significant difference in OS between LT and TKI groups (median overall survival, 28 vs 23months; hazard ratio, 0.75; 95% confidence interval, 0.52-1.07). In patients with 1 to 4 BMs, the LT group showed significantly better OS compared with the TKI group (median overall survival, 35 vs 23months; hazard ratio, 0.54; 95% confidence interval, 0.32-0.90). There was no difference in OS between the LT and TKI groups for patients with ≥5 BMs. Multivariable analysis showed that upfront LT yielded significantly better OS for patients with 1 to 4 BMs. Upfront LT followed by EGFR-TKI is more effective than upfront EGFR-TKI for the survival of untreated patients harboring EGFR mutations with 1 to 4 BMs.