Abstract: Background and purpose: In prostate cancer, the high expression of epidermal growth factor receptor (EGFR) gene is confirmed to indirectly promote the migration of tumor cells and is associated with a shorter metastasis-free survival. However, majority of previous research on the EGFR gene focused on the mechanism and rarely established links with clinical indicators. This study aimed to compare the genotype differences of EGFR gene in the western countries and Chinese prostate cancer patients, to explore the correlation between clinicopathological characteristics and EGFR gene polymorphism. Methods: The polymorphism of EGFR (RS884419) gene in peripheral blood leukocyte DNA of 182 prostate cancer patients who were treated in Fudan University Shanghai Cancer Center from 2014 to 2019 was detected to compare genotype differences of EGFR gene in prostate cancer patients between Chinese and the western populations, and to explore the correlation between clinicopathological and basic characteristics and EGFR gene polymorphism. Results: Compared with patients in the variant group with EGFR (rs884419) genotypes AA and AG, patients in the normal group with genotype GG had a higher proportion of distant metastases (M ₁ stage) at diagnosis (65.3% vs 84.2%, P ＜ 0.05); EGFR (rs884419) gene polymorphism had no correlation with age at diagnosis, prostate-specific antigen at diagnosis, metastatic load and Gleason score (P ＞ 0.05). Compared with American prostate cancer patients, the mutation frequency of EGFR (rs884419) gene was higher (20.4% vs 79.1%, P ＜ 0.05). Conclusion: The M ₁ stage of patients at diagnosis is higher in the normal EGFR genotype group than in the variant group, suggesting that the difference in EGFR gene expression may be involved in the occurrence and development of prostate cancer metastasis. According to the genotype, the distant metastasis status of patients at the diagnosis can be predicted theoretically. And due to the high frequency of mutations in the Chinese patients, EGFR genotype has a stronger predictive value for treatment efficacy than it does in the western population.

Key words:  Prostate cancer, Epidermal growth factor receptor, rs884419, Gene polymorphism, Clinicopathological characteristics