The study included patients treated between 2018 and 2023. Of the 275 participants, 183 were classified as having de novo stage IV disease and 92 as having postoperative recurrence. The difference in progression-free survival was statistically significant, with a reported P value below 0.0001, and the difference in overall survival was also statistically significant at P = 0.0030.

Both analyses compared patients who received first-line osimertinib, making the study a prognostic comparison within a treated cohort rather than a direct test of the drug against another treatment or an untreated control group. Analyses by EGFR mutation subtype showed that the survival pattern was consistent among patients with an exon 19 deletion and those with the L858R mutation. The postoperative-recurrence association with longer survival also remained statistically significant after adjustment for age, sex, Eastern Cooperative Oncology Group performance status and EGFR mutation subtype.

These results indicate that the measured demographic, clinical and molecular factors did not fully account for the observed difference. However, the retrospective design leaves the contribution of other differences between the groups unresolved, and the study cannot determine whether postoperative recurrence itself produced the more favorable outcomes. The researchers additionally examined whether the tumor–node–metastasis ninth-edition M1 subclassification was associated with outcomes among patients with de novo stage IV disease.

In exploratory subgroup analyses, those classified as M1c2 had numerically shorter survival than patients in the other M categories. The authors described M1c2 as representing high multi-organ metastatic burden, but the comparative analysis was exploratory and the findings require validation. Overall, the study reports a substantial survival association between postoperative recurrence and comparatively favorable outcomes in EGFR-mutant lung adenocarcinoma treated with osimertinib.

Its strongest evidence comes from the significant comparisons of progression-free and overall survival, together with the persistence of the association after adjustment for several measured characteristics and across two EGFR mutation subtypes. Nevertheless, the analysis was based on retrospective clinical data from six institutions, and its subgroup results remain exploratory.

Subject of Research: Comparative survival in surgically recurrent versus de novo stage IV EGFR-mutant lung adenocarcinoma treated with osimertinib

Article Title: Survival advantage of postoperative recurrence compared to de novo stage IV disease in EGFR-mutant lung adenocarcinoma treated with osimertinib: a multicenter retrospective study

Article References: Sato, M., Tanaka, I., Hori, K., Koyama, J., Kodama, Y., Matsui, A., Miyazawa, A., Miyamatsu, S., Asano, S., Hibino, Y., Yokoyama, T., Kimura, T., Yoshida, N., Sato, M., & Ishii, M. (2026). Survival advantage of postoperative recurrence compared to de novo stage IV disease in EGFR-mutant lung adenocarcinoma treated with osimertinib: a multicenter retrospective study. BMC Cancer. https://doi.org/10.1186/s12885-026-17153-1

Image Credits: AI Generated

DOI: 10.1186/s12885-026-17153-1

Keywords: EGFR mutations, lung adenocarcinoma, osimertinib, postoperative recurrence, stage IV disease, progression-free survival, overall survival, retrospective cohort, TNM staging, M1c2 metastases, Survival, advantage