The focus  of  this research is to study whether  the tumour   size is one of the vital variables that  effect on the  overall survival  rate  of  breast cancer cases after stratified  by the  hormone  receptor  . a sample of six    hundred  and sixty-three  woman cases  with breast  cancer aged  between 23 to 83 years was  examined . cox  proportional hazard  regression  model  is used . unadjusted and adjusted model ( adjusting by age, menopause  status  and  lymph  node status) are fitted. All analyses  are  stratifited by  factors that  increase  the mortality  rate  for  the  breast  cancer  patients.