The role of prostaglandin E receptor 2 and epidermal growth factor receptor in esophageal squamous cell carcinoma patients with (pN+) regional lymph node metastasis

BACKGROUND: To find the relationship between prostaglandin E receptor 2 (EP(2)) and epidermal growth factor receptor (EGFR) in esophageal squamous cell carcinoma (ESCC) patients with regional lymph nodes metastasis (pN+) who had undergone curative resection, and to analyze them in the role of judging prognosis. METHODS: Sixty-three patients with ESCC who underwent attempted curative esophagectomy with lymph node metastasis were collected. Immunohistochemistry (IHC) was used to analyse the expression of EP(2) and EGFR in tumor tissues. We analyzed the relationship between the two markers. Furthermore, we analyzed the role of EP(2) and EGFR in disease-free survival (DFS) and overall survival (OS). RESULTS: The expression rate of EP(2) and EGFR in this study were 73.0%, 85.7%, respectively. And the EP(2) status was closely related with the expression of EGFR in tumor tissues (χ(2)=0.260, P=0.011). The patients with EP(2) or EGFR positive expression had a shorter DFS and OS than the negative group. Further analysis found EGFR is an important prognostic factor for DFS and OS (P<0.001), the expression of EP(2) was related with PFS (P=0.048), but it was not an independent influencing factors for OS (P>0.05). CONCLUSIONS: The expression of EP(2) and EGFR were high in tumor tissues of (pN+) ESCC, and they are playing a key role in the prognosis of ESCC patients with local lymph node metastases.