Post-Progression Survival Is Strongly Associated with Overall Survival in Patients Exhibiting Postoperative Relapse of Non-Small-Cell Lung Cancer Harboring Sensitizing <i>EGFR</i> Mutations

• Main Authors: Hisao Imai, Ryoichi Onozato, Maiko Ginnan, Daijiro Kobayashi, Kyoichi Kaira, Koichi Minato
• Format: Article
• Language: English
• Published: MDPI AG 2021-05-01
• Series: Medicina
• Subjects: EGFR-TKI; <i>EGFR</i> mutation; non-small-cell lung cancer; overall survival; postoperative relapse; post-progression survival
• Online Access: https://www.mdpi.com/1648-9144/57/5/508

<i>Background and Objective</i>: Patients with advanced non-small-cell lung cancer (NSCLC) harboring sensitizing epidermal growth factor receptor (<i>EGFR</i>) mutations show a good response to EGFR-tyrosine kinase inhibitors (EGFR-TKIs). The subsequent treatments influence the evaluability of the efficacy of front-line therapy on overall survival (OS). Consequently, we evaluated the associations of relapse-free survival (RFS) and post-progression survival (PPS) with OS in patients who exhibited postoperative relapse of <i>EGFR</i>-mutated NSCLC. <i>Materials and Methods</i>: We analyzed the data of 35 patients with <i>EGFR</i>-mutated NSCLC who underwent complete resection between January 2007 and June 2019. The correlations of RFS and PPS with OS were evaluated at the individual patient level. <i>Results:</i> Linear regression and Spearman’s rank correlation analyses demonstrated that the PPS highly correlated with OS (<i>r</i> = 0.91, <i>p</i> < 0.05, <i>R</i>² = 0.85), whereas the RFS weakly associated with OS (<i>r</i> = 0.36, <i>p</i> < 0.05, <i>R</i>² = 0.25). Age and performance status at relapse were significantly associated with PPS. <i>Conclusion</i>: Overall, PPS was more strongly and significantly associated with OS than RFS. These results suggest that the OS of our cohort may be affected by treatments, besides postoperative relapse. However, larger-scale prospective studies are needed to confirm these results.