Introduction: The esophageal squamous cell carcinoma (ESCC) is the predominant pathological type and accounts for more than 80 % of esophageal cancer in China. The successful use of anti-epidermal growth factor receptor (EGFR) treatment in head and neck squamous cell carcinoma provides the rationale for introducing anti-EGFR targeting treatment in ESCC. One of our prospective phase II clinical trials analyzed the efficacy of nimotuzumab, an anti-EGFR agent, combined with chemotherapy (paclitaxel and cisplatin) to treat unresectable ESCC.
Materials and methods: We analyzed the correlation of the clinical response with EGFR expression by immunohistochemical staining (IHC).
Results: Totally 55 tumor samples were analyzed. 18/55 (32.7 %) cases were with high EGFR expression while the other 37/55 (67.3 %) cases were with low to moderate EGFR expression. The expression of EGFR was not related to gender, age, tumor location, tumor differentiation and clinical stage of disease. The objective response rate (ORR) in high EGFR expression group was 55.6 % (10/18) while that in low to moderate EGFR expression group was 54.1 % (20/37) (P = 0.57). Both the progression-free survival (PFS) and overall survival (OS) in high EGFR expression group were much shorter than those in low to moderate EGFR expression group (PFS: 5.8 ± 0.5 vs. 11.0 ± 2.8 months, P = 0.007; OS: 9.7 ± 0.5 vs. 21.5 ± 1.5 months, P = 0.03).
Conclusions: The results showed that over-expression of EGFR was related to poor survival of ESCC. The over-expression of EGFR by IHC might not be an ideal predictive biomarker of nimotuzumab treatment. Other EGFR pathway-associated molecules should be analyzed in further studies.
Keywords: Epidermal growth factor receptor; Esophageal squamous cell carcinoma; Nimotuzumab.