RESUMEN
Objectives: The study aims to evaluate the efficacy and safety of thoracic radiotherapy in epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI)-treated patients with stage IV non-small-cell lung cancer (NSCLC). Methods: Patients with non-oligometastatic NSCLC harboring EGFR mutations were recruited. All patients received the first-generation TKI treatment with or without radiotherapy. The irradiated sites included primary and/or metastatic lesions. Of all the patients who underwent thoracic radiotherapy, some received radiotherapy before EGFR-TKI resistance, others received radiotherapy after progressive disease. Results: No statistically significant difference was observed in progression-free survival (PFS) (median 14.7 versus 11.2 months, p = 0.075) or overall survival (OS) (median 29.6 versus 40.6 months, p = 0.116) between patients treated with EGFR-TKIs alone and those with additional radiotherapy to any sites. However, EGFR inhibitors with thoracic radiation significantly improved OS (median 47.0 versus 31.0 months, p < 0.001) but not PFS (median 13.9 versus 11.9 months, p = 0.124). Moreover, longer PFS (median 18.3 versus 8.5 months, p < 0.001) was achieved in the preemptive thoracic radiation cohort than in the delayed thoracic radiation cohort. However, OS was similar between the two cohorts (median 40.6 versus 52.6 months, p = 0.124). The lower incidence rate of grade 1-2 pneumonitis occurred in preemptive radiation cohort (29.8% versus 75.8%, p < 0.001). Conclusion: Non-oligometastatic NSCLC patients with EGFR mutations benefited from thoracic radiotherapy while using EGFR inhibitors. Preemptive thoracic radiotherapy could be a competitive first-line therapeutic option due to superior PFS and favorable safety.
RESUMEN
PURPOSE: This study aimed to explore the clinical value of SBRT for primary lung lesions of EGFR-mutant NSCLC patients with non-oligometastatic disease during first-line EGFR-TKI treatment. METHODS: We identified patients with stage IV EGFR-mutant non-oligometastatic NSCLC who were suitable to receive SBRT for the primary tumors after EGFR-TKI treatment. All selected patients were treated with first-line EGFR-TKIs and SBRT for their primary lesions. The primary endpoints were the progression-free survival 1 (PFS1, time of first TKI dose relative to disease progression based on RECIST) and PFS2 (time of first TKI dose relative to disease progression after SBRT). The secondary endpoints were overall survival (OS) and safety. RESULTS: Seventy-nine patients were enrolled, including 45 patients who received SBRT for their primary tumor at the maximal response of EGFR-TKI (the preemptive RT group) and 34 patients who received SBRT for their primary tumor after the occurrence of oligoprogression (the delayed RT group). The preemptive RT group had a significantly better median PFS1 than the delayed RT group (22.3 months vs. 12.9 months, P = 0.0031). The median PFS2 in the preemptive RT and delayed RT groups were 22.3 and 28.9 months, respectively (P = 0.17). The median OS did not differ significantly between the preemptive RT group and the delayed RT group (46.6 versus 51.3 months, P = 0.54). No severe toxicities (≥ grade 3) were recorded. CONCLUSION: This real-world study showed that preemptive RT to primary lung tumors is a feasible option for selected patients with EGFR-mutant non-oligometastatic NSCLC who had stable disease during first-line EGFR-TKI treatment, and that it significantly improved PFS.