Based on the present analysis of long-term follow-up after operation, PLC may also be an independent prognostic factor. In particular, the PLC status of patients with stage I disease or adenocarcinoma type has an important impact on survival. PLC-positive findings may be a high risk for postoperative pleural recurrence. For PLC-positive patients with stage I disease, careful serial follow-up for more than 5 years is required while paying attention to late pleural recurrence.