Identification Prognostic factors for disease-free survival in breast Cancer patients

Breast cancer is the most common cancer in women and the second leading cause of cancer death after lung cancer. Survival rate is an important index to evaluate the effects of treatment and diagnostic methods of breast cancer. The purpose of this study is to investigate the factors affecting the survival of breast cancer patients. This study is a kind of survival analysis studies. During 2006-2009, 347 women with breast cancer were treated in Fayazbakhsh Hospital, Tehran. All patients were followed up until 2012 April. A cox regression model was used to determine the prognostic factors. All statistical methods run in R software version 2.10. In this study, the mean age of patients was 49.9 years with a standard deviation of 11.01. The result of this study showed that grade and number of involved lymph nodes were prognostic factors (p<0.05). Age, size of tumor, PR, ER, and HER2 were not identified as prognostic factors (p>0.05). Hazard ratio of metastasis or death for involved lymph nodes (within 3- 10) was HR= 2.5 times of patients with zero involved lymph nodes(CI%95(1/03, 1/69)).Patents with grade 3 had risk of metastasis or death HR=1.5 times of grade 2(CI%95(1/46, 3/97)). The education of women for early diagnosis by Health centers is necessary.