ESR1 and neoplasm: To evaluate the association between the creatinine-cystatin C ratio and 1-year all-cause mortality, we constructed three Cox proportional hazards models (Table 2): Unadjusted model, No covariates were adjusted; Model 1, Adjusted for age and BMI based on the unadjusted model; Model 2, Further adjusted for tumor diameter, PA, targeted therapy, surgery, chemotherapy, radiotherapy, ER, PR, HER2, endocrine therapy, Ki67, and clinical stage in addition to Model 1.