Late recurrence of non-small cell lung cancer more than 5 years after complete resection: Incidence and clinical implications in patient follow-up

Background: The purpose of this study was to evaluate the risk of late recurrence in patients who had undergone complete resection for non-small cell lung cancer (NSCLC) and remained recurrence-free for ≥ 5 years. Methods: Between 1993 and 2002, 1,358 patients with NSCLC underwent complete primary tumor resection and systematic lymph node dissection. Of these, 819 patients remained recurrence-free for 5 years. Recurrence-free probability was estimated from the benchmark of 5 years after primary tumor resection to the date of first recurrence or last follow-up, using the Kaplan-Meier method. Multivariate Cox regression was used to test the relationship of recurrence-free probability to various clinicopathologic factors. Results: Of the 819 patients who were free of recurrence at 5 years, 87 (11%) developed a subsequent recurrence. The recurrence-free probabilities at 3 years and 5 years from the point of 5 years after primary tumor resection were 92% and 87%, respectively. The 5-year recurrence-free probabilities from the point of 5 years after primary tumor resection were 81% for patients with intratumoral vascular invasion(P < .001), and 89%, 84%, and 65% for patients with N0, N1, and N2 cancers, respectively(P < .001). Multivariate Cox analysis demonstrated that intratumoral vascular invasion and nodal involvement significantly influenced recurrence 5 years after complete resection(P = .030, P = .022, respectively). Conclusions: Patients with NSCLC with selected tumor characteristics have a significant risk of late recurrence. Therefore, 5 years might not be a sufficient amount of time to declare that NSCLC has been cured.