Correlation of epidermal growth factor receptor expression in esophageal cancer tissues with sensitivity of radical radiotherapy and prognosis of patients / 肿瘤研究与临床

ABSTRACT

Objective:To analyze the correlation of epidermal growth factor receptor (EGFR) expression in esophageal cancer tissues with sensitivity of radical radiotherapy and prognosis of patients.Methods:A total of 98 esophageal cancer patients admitted to the Affiliated Hospital of Jiangnan University from January 2017 to July 2019 were selected, and all patients received radical radiotherapy. The efficacy was assessed after 4 weeks of radiotherapy, partial remission (PR) + complete remission (CR) was treated as the sensitive group and disease progression (PD) + stable disease (SD) was treated as the tolerated group. The expression of EGFR in cancer tissues and paraneoplastic tissues (more than 5cm from the margin of cancer tissues) was measured by using immunohistochemistry. The expression of EGFR in cancer tissues and paraneoplastic tissues and the clinicopathological characteristics of the sensitive and tolerant groups were compared. Cox proportional risk model was used to analyze the factors influencing the prognosis of esophageal cancer patients; the Kaplan-Meier method was used to analyze the relationship between EGFR expression in cancer tissues and prognosis of patients.Results:The positive expression rate of EGFR in esophageal cancer tissues (66.3%, 65/98) was higher than that in paraneoplastic tissues (29.6%, 29/98), and the difference between the two groups was statistically significant (χ 2=26.49, P < 0.001). All 98 patients successfully completed radical radiotherapy, including 4 cases of CR, 60 cases of PR, 26 cases of SD and 8 cases of PD. The proportion of patients with highly differentiated and tumor length ≤1.5 cm in the sensitive group was higher than that in the tolerant group, and the differences were statistically significant (all P < 0.05). The positive expression rate of EGFR in cancer tissues in the sensitive group (56.3%, 36/64) was lower than that in the tolerant group (85.3%, 29/34), and the difference between the two groups was statistically significant ( χ2=8.39, P < 0.001). Multifactorial Cox regression analysis showed that poor differentiation, tumor long diameter >1.5 cm, and positive EGFR expression were independent risk factors for overall survival in patients with esophageal cancer (all P < 0.05). The difference in overall survival between patients with positive and negative EGFR expression was statistically significant ( χ2=9.70, P = 0.002). Conclusions:Highly-expressed EGFR in esophageal cancer tissues may suggest low sensitivity of radical radiotherapy and poor prognosis of patients.