Epidermal growth factor receptor is a prognosis predictor in patients with esophageal squamous cell carcinoma

Our previous study indicated the survival rate for esophageal squamous cell cancer (ESCC) patients in stage III and positive lymph node groups with postoperative radiation therapy was significantly increased compared with surgery alone. But a predictive biomarker was needed to identify the patients who would benefit from postoperative radiotherapy. This study aims to evaluate epidermal growth factor receptor (EGFR) as an indicator to predict the prognosis of ESCC and to identify the patients who would benefit from postoperative radiotherapy.

Tissue samples were collected from our previous randomized study: 243 in the surgery alone group and 198 in the surgery plus radiotherapy group. Expression of EGFR was analyzed by immunohistochemical staining.

The expression of EGFR is correlated with depth of tumor invasion (p=0.005), lymph node metastasis (p<0.001), and pathologic stage (p<0.001). The survival rate of patients with high EGFR expression is significantly lower than that of patients with low EGFR expression (p=0.000). Notably, in stage IIA cases, the 5-year survival rate is 57.6% in the low EGFR expression group and 36.6% in the high expression group (p=0.020). EGFR is one of the independent variants that influence the prognosis. Moreover, for high EGFR expression patients the survival rate of the surgery plus radiotherapy group is higher than that of the surgery alone group (p=0.034).

Expression of EGFR can be a prognostic predictor for ESCC. Patients with high expression of EGFR may benefit from postoperative radiation therapy.