Supplementary Material for: Lymphovascular Invasion Increases the Risk of Nodal and Distant Recurrence in Node-Negative Stage I–IIA Non-Small-Cell Lung Cancer

Objectives: Despite complete surgical resection, 30–40% of patients with stage I–IIA non-small-cell lung cancer (NSCLC) have recurrences. We aimed to elucidate the effect of lymphovascular invasion (LVI) on the prognosis and patterns of recurrence in patients with pathologically confirmed T1–2N0 NSCLC. Methods: We evaluated 381 patients who underwent complete resection and were diagnosed with pathologic T1–2N0 NSCLC between March 2000 and January 2012. Local recurrence, nodal recurrence, and distant metastasis were defined and analyzed. Results: LVI was present in 72 patients (18.9%). The 5-year disease-free survival (DFS) for all patients was 69.9%. Patients with LVI showed a significant decrease in 5-year DFS (47.3 vs. 74.4%, p < 0.001). LVI was a significant prognostic predictor in multivariate analysis (p = 0.003). The patients with LVI showed a significantly increased 5-year cumulative incidence of nodal recurrence (22.5 vs. 8.7%, p < 0.001) and distant metastasis (30.4 vs. 14.9%, p = 0.004). However, no difference was shown between the two groups in the 5-year cumulative incidence of local recurrence (p = 0.416). Conclusions: LVI is a negative prognostic factor in patients with stage I–IIA NSCLC. The presence of LVI significantly increases the risk of nodal and distant recurrence.