Fig. 2From: Time trend of mediastinal lymph node dissection in stage IA non-small cell lung cancer patient who undergo lobectomy: a retrospective study of surveillance, epidemiology, and end results (SEER) databaseKaplan–Meier survival curve in T1b patient groups (a) OS curve in period 2003–2008, (b) LCSS curve in period 2003–2008, (c) OS curve in period 2009–2013, and (d) LCSS curve in period 2009–2013Back to article page