Abstract
INTRODUCTION: Esophageal squamous cell carcinoma (ESCC) accounts for 80% of all esophageal cancers worldwide. It is the most common histological type of esophageal carcinoma in low-resource countries. ESCC is prevalent in Asian countries, accounting for more than 95% of esophageal cancers. The epidermal growth factor receptor (EGFR) is involved in cancer development, as its gene is often mutated and/or amplified in cancer cells. According to recent statistics, esophageal cancer is the eighth most common cancer in Iran.
METHODS: In this retrospective study, we assessed EGFR overexpression, using immunohistochemistry (IHC) in 68 patients with ESCC, undergoing neoadjuvant chemoradiotherapy and esophagectomy in 2011-2014. The treatment protocol included external beam radiotherapy (40 Gy), concomitant with cisplatin 20mg/m2 and 5- fluorouracil (5-FU) 1000 mg/m2 for 4 consecutive days during the first and fourth weeks of treatment. To compare the two groups (EGFR positive and negative) in terms of complete pathologic response, Chi-square test was performed using SPSS version 16.
RESULTS: The median age of the patients was 59 years (range: 27–70 years), with a female-to-male ratio of 1.06. Overall, 70% of the subjects showed EGFR overexpression. Complete pathologic response to neoadjuvant treatment was significantly higher in EGFR-positive patients (40% vs. 15.8%, P = 0.05). In all cases, 1- and 3-year overall survival rates were 86.6% ± 4.1 and 48% ± 6.9, respectively. The 1- and 3-year disease free survival rates were calculated as 71.8% ± 5.4 and 44.3% ± 6.5, respectively. The overall survival rate was relatively higher in cases with EGFR overexpression, although the difference was not statistically significant (5-year survival rate: 47.9 ± 8.2 vs. 30.9 ± 13, P = 0.23).
CONCLUSION: EGFR overexpression was reported in the majority of patients with ESCC in northeastern Iran. Moreover, EGFR overexpression was significantly associated with complete pathologic response.