Figure 6. Overall survival curves according to dissection method in the negative plexus invasion subgroup. The survival rate was significantly improved (P=0.004) in the left posterior approach group (LPA) (1- and 3-year survival rates: 92.8% (n=23) and 64.2% (n=9), respectively) as compared to the control group (1- and 3-year survival rates: 82.1% (n=23) and 21.4% (n=6), respectively). The log-rank test was applied.