HIF1A and metastatic malignant neoplasm in the lymph nodes: Although there was no difference in the pathological indexes of the degree of tumor differentiation, depth of myometrial invasion and tumor stage between the two groups (due to the small sample size and bias), previous studies (43, 44) showed that the tumors with higher expression of HIF-1α had lower tissue differentiation, deeper myometrial invasion, higher probability of lymph node metastasis and higher malignant degree of tumor.