Prognostic significance of epidermal growth factor receptor in esophageal squamous cell carcinomas

The prognostic value of epidermal growth factor (EGF) receptor level was studied in 32 patients with esophageal squamous cell carcinoma. The EGF receptor levels of tumors were measured by iodine 125 (125I)-EGF binding assay, and the patients subsequently were divided into two groups: a group with high EGF binding capacities (greater than or equal to 2.5% of input), and a group with low EGF binding capacities (less than 2.5% of input). The cumulative survival rates for the two groups were calculated by the Kaplan-Meier method. The generalized Wilcoxon test indicated that the survival rate of the high EGF binding group was significantly lower than that of the low EGF binding group (P less than 0.05). In tumors from two patients with the highest EGF receptor levels, EGF receptor gene amplification was observed. These patients developed mediastinal lymph node metastasis and died 4 and 11 months after surgery, respectively. These results suggest that elevated EGF receptor level is a significant prognostic indicator for esophageal squamous cell carcinoma.