Impact of timing and initial recurrence site on post-recurrence survival in resected non-small cell lung cancer

Introduction High recurrence rate following curative surgery for non-small cell lung cancer (NSCLC) presents a major clinical challenge. Understanding the site and timing of recurrence and their impact on post-recurrence survival (PRS) is important for optimal postoperative surveillance and therapeutic intervention. In this study, we investigated the influence of the time to recurrence (TTR) and initial recurrence site on PRS. Materials and Methods This multicentre prospective cohort study included patients who experienced recurrence after NSCLC resection between 2010 and 2015. The relationship between TTR and initial recurrence site, and their impact on PRS, was further evaluated. The hazard ratio (HR) for PRS was analysed using the Cox proportional hazards model. Results Among 495 patients, the median TTR was 14 (range, 1–158) months; the mode of recurrence was 11 months. Early recurrence within 6 months was observed in 17% of patients, and 68% of patients showed recurrence within 2 years post-surgery. The HR for PRS was the highest in patients with a TTR within 6 months, and a noticeable decline was observed after the first 6 months. The HRs of TTRs beyond 2 years were not significantly different. The liver was a significantly unfavourable prognostic site for metastases (HR 2.2; P = .006), and metastases frequently recurred within 6 months after surgery. The timing of brain metastasis did not significantly impact the PRS. Conclusion Earlier recurrence after surgery was associated with shorter PRS. In contrast, recurrences occurring >2 years after surgery do not significantly affect PRS.