Abstract: Objective To explore the role of albumin to fibrinogen ratio (AFR) in the prognosis assessment of patients with breast cancer. 
Methods Clinical data of 736 breast cancer patients treated in our hospital were retrospectively analyzed. AFR was detected before surgery, and they were grouped according to AFR. The overall survival (OS) and survival rate of patients were recorded, and Cox regression was used for survival analysis. 
Results The follow-up period ranged from 12 to 81 months, with a median follow-up period of 65 months. Eighty-three patients (11.28%) died, and the overall survival period was (66.23 ± 12.38) months. The receiver operating characteristic (ROC) curve showed that the area under the ROC curve (AUC) of preoperative AFR in predicting the death of breast cancer patients was 0.727 (95%CI: 0.663-0.781, P＜0.001), and the cut-off value was 13.15. In addition, 736 patients were divided into high AFR group (＞13.15, n=538) and low AFR group (≤13.15, n=198). The OS, survival rate, age, albumin, leukocytes, and platelets of the low AFR group were lower than those of the high AFR group, while fibrinogen (FIB), TNM stage Ⅲ, nuclear grade 3, and vascular tumor thrombus were higher than those of the high AFR group, suggesting significant differences (P＜0.05). Univariate analysis showed that FIB, AFR, platelet, TNM staging, nuclear grade, presence or absence of vascular tumor thrombus, and difference in positive estrogen receptor/progesterone receptor (ER/PR) were statistically significant (P＜0.05). The results of multivariate Cox regression analysis showed that AFR≤13.15, vascular tumor thrombus and TNM stage Ⅲ were the risk factors for the prognosis of breast cancer patients, and positive ER/PR was the protective factor. 
Conclusion The decrease in AFR indicates a poor prognosis for breast cancer patients. AFR with 13.15 as a critical value has a good predictive effect on breast cancer survival rate. 

Key words: breast neoplasms, albumins, fibrinogen