Long-term Survival and Prognostic Factors of Breast Cancer

Abstract

Background: Breast cancer survival rate is an important index for assessment of treatment effect in reducing the mortality. We aimed to determine the fifteen-year survival rate for breast cancer at a referral center in Iran and its correlated factors. Methods: This survival study enrolled patients with breast cancer who referred to Motamed Cancer Institute (MCI) from 1998 to 2016. The survival rate was calculated using the Kaplan-Meier method. The relationship of demographic, clinical and therapeutic factors with overall survival (OS) was studied using Cox’s proportional hazard model. Results: Totally, 3443 patients were studied. Their mean age and follow-up period were 47.7 (±11.43) years and 61.66 (±52.1) months, respectively. The median follow-up time was 48.4 months (range: 1-413 months), 49.7% of the patients had high school or higher education, and 71.3% presented in the early stage of the disease. Death occurred in 505 (14.7%) of the patients. The overall 2-, 5-, 7-, 10- and 15-year survival rates were 93%, 82%, 78%, 74%, and 66%, respectively. Lymph node involvement (HR=2.07; 95% CI: 1.38–3.09), tumor size≥5 cm (HR=2.83; 95% CI: 1.59–2.04), being single/divorced/widowed (HR=1.65; 95% CI: 1.13–2.4), and education level