Comparing the efficacy of concurrent EGFR-TKI and whole-brain radiotherapy vs EGFR-TKI alone as a first-line therapy for advanced EGFR-mutated non-small-cell lung cancer with brain metastases: a retrospective cohort study

Background Non-small-cell lung cancer (NSCLC) is a global public health problem, and brain is a common metastatic site in advanced NSCLC. Currently, whole-brain radiotherapy (WBRT) remains a major treatment for brain metastases, while EGFR-tyrosine kinase inhibitor (TKI) is the standard treatment for advanced NSCLC harboring EGFR mutations, which is also effective for brain metastases. However, whether EGFR-TKIs plus radiotherapy is superior to EGFR-TKIs alone for the treatment of advanced EGFR-mutant NSCLS with brain metastases remains controversial. This study aimed to compare the efficacy of concurrent EGFR-TKIs and WBRT vs EGFR-TKI alone in a retrospective cohort of advanced EGFR-mutant NSCLS with brain metastases. Patients and methods The medical records of 104 treatment-naive, advanced EGFR-mutant NSCLC patients with brain metastases were retrospectively reviewed, and there were 56 patients undergoing concurrent EGFR-TKI and WBRT, and 48 patients given EGFR-TKI alone, including 20 cases with salvage WBRT upon brain metastasis progression. The survival prognosis was compared between the two cohorts. Results The baseline clinicopathologic factors were balanced between the two cohorts. After a median follow-up of 23 months, 35.6% of the study subjects survived. Concurrent EGFR-TKI and WBRT significantly improved the median intracranial PFS (iPFS) compared with EGFR-TKI alone (17.7 vs 11.0 months, P=0.015); however, no significant difference was seen in median overall survival between the two cohorts (28.1 vs 24.0 months, P=0.756). In addition, the median iPFS was found to significantly vary in the number of brain metastases (≤3 vs>3 metastases: 18.0 vs 12.5 months, P=0.044). Subgroup analysis showed that concurrent EGFR-TKI and WBRT improved median iPFS compared with EGFR-TKI alone in patients with more than three brain metastases (P=0.001); however, no significant difference was observed between the two regimens in patients with three or less brain metastases (P=0.526). Conclusion Our data demonstrate that concurrent EGFR-TKI and WBRT achieves longer iPFS than EGFR-TKI alone in advanced EGFR-mutant NSCLC with brain metastases. In advanced EGFR-mutant NSCLC with three or less brain metastases, EGFR-TKI alone may be an option as a first-line therapy.