Jun-Ho Lee

Background: Lazertinib is a third-generation tyrosine kinase inhibitor of epidermal growth factor receptor (EGFR-TKI) that selectively inhibit common EGFR mutation and T790M mutation in non-small-cell lung cancer (NSCLC) patients. No previous studies have compared lazertinib to platinum-based chemotherapy. We have compared lazertinib with platinum-based chemotherapy in EGFR-mutated NSCLC patients after previous EGFR-TKI therapy. Methods: We retrospectively compared 200 patients from LASER201, LASER301, and LASER-PMS studies to 334 patients who were treated with platinum-based chemotherapy after previous EGFR-TKI from the Samsung Medical Center. After propensity score matching (PSM), we selected 156 patients from each group. The primary outcome was progression-free survival (PFS), with overall survival (OS), objective response rate (ORR), and time to treatment discontinuation (TTD) as secondary outcomes. Results: The median follow-up of PFS was 15.61 months in the lazertinib group and 21.67 months in the external control group. The PFS was significantly longer in patients who were treated with lazertinib than those treated with platinum-based chemotherapy (10.97 months vs. 5.10 months; adjusted hazard ratio (HR) 0.40; 95% confidence interval (CI), 0.29–0.55; p < 0.01) after PSM. Lazertinib showed superior OS (32.23 months vs. 18.73 months; adjusted HR 0.45; 95% CI, 0.29–0.69; p < 0.001), ORR (64.1% vs. 47.4%), and TTD (11.66 months vs. 6.73 months; adjusted HR 0.54; 95% CI, 0.39–0.75; p < 0.001) compared to platinum-based chemotherapy. Conclusion: Based on this retrospective, external control study, lazertinib has demonstrated significantly better efficacy compared with platinum-based chemotherapy. The external controls provide important context to evaluate efficacy in single-arm studies.

We present the Pneumocystis pneumonia case of a 64-year-old man with no remarkable history except for hypertension, who had not undergone any treatment other than surgery. On postoperative day 7, high-resolution computed tomography findings revealed multifocal ground-glass opacifications with interlobular septal thickening in both lungs; therefore, atypical pneumonia was suspected. Polymerase chain reaction (PCR) test performed after bronchoalveolar lavage was positive for Pneumocystis jirovecii (P. jirovecii). Based on the PCR results, a final diagnosis of Pneumocystis pneumonia (PCP) was made. After treatment, he improved and was discharged. This is a unique case of PCP diagnosis in a non-immunocompromised patient, with no remarkable history except for hypertension, who had not undergone any treatment other than surgery for cancer. Thus, it is necessary to consider additional risk factors for PCP and timing of preventive treatment.