To investigate the prognostic value of serum epithelial cadherin（E-cad）and hypoxia-inducing factor（HIF-1α）levels in patients undergoing modified radical mastectomy.

A total of 112 patients who received modified radical mastectomy from June 2018 to June 2019 were included in the study. All patients received 2-year follow-up and were divided into a recurrence group and a non-recurrence group according to the recurrence situation within 2 years. χ² test and t test were used to compare the baseline data，preoperative serum E-Cad and HIF-1α levels of the two groups. The influence of preoperative serum E-Cad and HIF-1α on the prognosis of breast cancer was tested by COX regression analysis. Receiver operating characteristic curve（ROC）and decision curve were drawn to analyze the prognostic value of preoperative serum E-Cad and HIF-1α levels in modified radical mastectomy.

In 112 patients with breast cancer followed up for 2 years after modified radical surgery，23 cases recurred，the recurrence rate was 20.5%（23/112）. The TNM stage and the incidence of lymph node metastasis in recurrent group were higher than those in non-recurrent group，the tumor size and preoperative serum HIF-1α level were higher than those in non-recurrent group，and the preoperative serum E-Cad level was lower than those in non-recurrent group（P < 0.05）. COX regression analysis showed that high TNM stage，lymph node metastasis，large tumor and preoperative high HIF-1α level were risk factors for postoperative recurrence of breast cancer patients（HR=3.696，4.061，7.739，1.052，P < 0.05），and preoperative high E-Cad level was protective factor（HR=0.313，P < 0.05）；ROC curve was drawn，and the results showed that the AUC of preoperative serum E-Cad and HIF-1α were 0.835 and 0.781，respectively，for predicting the prognosis of breast cancer patients after modified radical surgery. The decision curve was drawn，and the results showed that the combined prediction of preoperative serum E-Cad and HIF-1α levels for prognosis after modified radical mastectomy of breast cancer patients was superior to the net benefit rate predicted by them alone within the threshold of 0.2-0.6.

The prognosis of patients with breast cancer after modified radical surgery is affected by the levels of serum E-Cad and HIF-1α before surgery，and the combined detection of the two has a high predictive value for the prognosis of patients with breast cancer after modified radical surgery.