Gene testing and prognosis in post-operative recurrent non-small-cell lung cancer: subgroup analyses of WJOG15421L

BACKGROUND: This study aimed to investigate the status of biomarker testing and prognosis in patients with post-operative recurrent non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: This retrospective multicenter study included 1500 patients with advanced or recurrent NSCLC from 29 institutions between July 2020 and June 2021. A post-operative recurrence subgroup analysis was carried out on 229 patients. The main focus was on the testing rate for biomarkers, including multigene testing. Survival analyses were also conducted. RESULTS: The median age of the study cohort was 74 years (range 40-92 years). Of the patients, 46.5% had stage I NSCLC, and 67% had adenocarcinoma. Median time from surgery to recurrence was 511 days, and 169 patients had distant metastases; 23% of the patients underwent rebiopsy to confirm recurrence. Multigene testing was conducted in 43.7% of the patients, and single-gene testing in 56.8%. Multigene testing was more frequent in cases with distant metastases (47%) compared with local recurrences (35%). No significant difference in testing success was observed between the resected preserved specimens and the rebiopsied recurrent specimens. Multigene testing was less likely if recurrence occurred >3 years after surgery. Post-operative recurrent patients had better overall survival than advanced-stage patients in both the overall cohort and the driver-positive subgroup. CONCLUSIONS: The rate of multigene testing in post-operative recurrent NSCLC cases was low despite the availability of sufficient surgical specimens. The further widespread adoption of multigene testing is one of the most critical challenges for improving resected patient outcomes along with recent advances in perioperative personalized medicine.