Relationship between gene amplification status of human epidermal growth factor receptor 2 and clinicopathological features in breast cancer

Objective To explore the relationship between gene amplification status of human epidermal growth factor receptor 2 (HER2) and its clinicopathological features in breast cancer, and to analyze the affecting factors of axillary lymph node metastasis in breast cancer. Methods The clinicopathological data of 262 patients with breast cancer at Tengzhou Central People's Hospital between January 2016 and March 2019 were collected, including age, tumor diameter, histological grade, pathological type, lymph node metastasis, tumor number, tumor location. The patients had routine pathology examination and the immunohistochemistry (IHC) result of HER2 was ++. The expressions of p53, Ki-67, estrogen receptor (ER), progesterone receptor (PR) were detected by using IHC. The gene amplification status of HER2 was detected by using fluorescence in situ hybridization (FISH). The relationship between gene amplification status of HER2 and clinicopathological features, the relationship between axillary lymph node metastasis and clinicopathological features was respectively analyzed. Results HER2 gene amplification-positive was detected in 69 cases of 262 breast cancer patients, and the positive amplification rate was 26.3%. The gene amplification status of HER2 was correlated with Ki-67 proliferation index and the expression of ER as well as PR, and the differences were statistically significant (χ 2=13.27, P 0.05). Among 262 cases of breast cancer, 106 (40.5%) cases had axillary lymph node metastasis. Lymph node metastasis was correlated with tumor diameter (χ 2=29.10, P 0.05). Conclusions HER2 gene amplification of breast cancer is associated with Ki-67 proliferation index, the expression of ER and PR. The tumor diameter is a factor for affecting axillary lymph node metastasis. Accurate judgment of the above indicators can better guide the treatment and evaluate the prognosis of breast cancer. Key words: Breast neoplasms; Human epidermal growth factor receptor 2; Gene amplification; Lymph node metastasis; Pathology, clinical