Clinicopathological analysis results suggested that the PTEN level was inversely related to tumor diameter (p = 0.020), tumor invasion (p = 0.004), TNM stage (p = 0.032), and lymph node metastasis (p = 0.017), whereas it showed no association with age and gender (Table 3), indicating that PTEN was a tumor suppressor of ESCC. Here, PTEN is linked to esophageal squamous cell carcinoma.