Background: There was no study investigating real-world utilization and outcome of LCT in Osimertinib-treated NSCLC with oligo-residual disease. This study was to analyze the clinical value of local consolidative therapy (LCT) in Osimertinib-treated non-small cell lung cancer (NSCLC) patients with oligo-residual disease. Methods: Patients receiving standard Osimertinib treatment and developing oligo-residual disease (five or fewer residual metastatic lesions) were retrospectively reviewed. Local therapies performed to the oligo-residual tumor lesions or primary lung site before Osimertinib treatment failure were considered as LCT. Results: Of 108 patients recruited, first-line and second-line Osimertinib were administered in 25 and 83 patients, respectively, while LCT was performed in 14 patients. With a median follow-up of 43.6 months, 69 patients developed progressive disease. LCT significantly improved progression-free survival (PFS) (NR vs 12.8 months, p=0.01) and was independently associated with prolonged PFS (HR=0.29, 95%CI 0.12 to 0.68, p=0.004). Patients receiving LCT had a numerically longer overall survival (OS) (85.8 vs 77.1 months, p=0.58) and after adjusting for potentially confounding factors, LCT was associated with a non-significantly prolonged OS (HR=0.37, 95%CI 0.12-1.16, p=0.089). Pattern of failure analyses indicated that progressive disease developed at the originally existed oligo-residual lesions in 76.2% of the 63 patients who didn’t receive LCT and had Osimertinib treatment failure. Of note, 7 (70%) of the 10 patients who had oligo-residual cranial disease but didn’t receive LCT, developed more than five progressive lesions in the brain, which were no longer suitable for stereotactic radiosurgery. Conclusion: Among Osimertinib-treated NSCLC patients having oligo-residual lesions, LCT could improve local control and significantly increase PFS, which need to be verified by further investigations.

Background: There was no study investigating real-world utilization and outcome of LCT in Osimertinib-treated NSCLC with oligo-residual disease. This study was to analyze the clinical value of local consolidative therapy (LCT) in Osimertinib-treated non-small cell lung cancer (NSCLC) patients with oligo-residual disease.Methods: Patients receiving standard Osimertinib treatment and developing oligo-residual disease (five or fewer residual metastatic lesions) were retrospectively reviewed. Local therapies performed to the oligo-residual tumor lesions or primary lung site before Osimertinib treatment failure were considered as LCT.Results: Of 108 patients recruited, first-line and second-line Osimertinib were administered in 25 and 83 patients, respectively, while LCT was performed in 14 patients. With a median follow-up of 43.6 months, 69 patients developed progressive disease. LCT significantly improved progression-free survival (PFS) (NR vs 12.8 months, p=0.01) and was independently associated with prolonged PFS (HR=0.29, 95%CI 0.12 to 0.68, p=0.004). Patients receiving LCT had a numerically longer overall survival (OS) (85.8 vs 77.1 months, p=0.58) and after adjusting for potentially confounding factors, LCT tended to increase OS (HR=0.37, 95%CI 0.12-1.16, p=0.089). Pattern of failure analyses indicated that progressive disease developed at the originally existed oligo-residual lesions in 76.2% of the 63 patients who didn’t receive LCT and had Osimertinib treatment failure. Of note, 7 (70%) of the 10 patients who had oligo-residual cranial disease but didn’t receive LCT, developed more than five progressive lesions in the brain, which were no longer suitable for stereotactic radiosurgery. Conclusion: Among Osimertinib-treated NSCLC patients having oligo-residual lesions, LCT could significantly improve PFS and has a tendency to prolong OS, which need to be verified by further investigations.