Figure 3.

Analysis of survival rates of patients with esophageal squamous cell carcinoma according to protein tyrosine kinase 7 (PTK7) immunohistochemical staining grade. (a) Kaplan–Meier curves for recurrence‐free survival of each grade. (b) Kaplan–Meier curves for overall survival of each grade. Grade 1, weak staining or fewer than 40% of tumor cells stained; grade 2, moderate to strong staining and 40–70% of tumor cells stained; grade 3, moderate to strong staining and more than 70% of tumor cells stained.