Survival rates of breast cancer: a hospital-based study from northeast of Thailand.

A retrospective cohort study was carried out with 340 female breast cancer at a teaching university in northeast of Thailand recruited and followed-up until the end of 2006. Survival probabilities were estimated using the Kaplan-Meier method. 161 cases were alive after five years and 58 patients were lost to follow-up. The overall observed survival rates at 1, 3 and 5 years were 83.3%, 59.9% and 42.9%, respectively. When analysis was conducted for stage combined into 2 groups, early (stage I, II and unknown) and late (stage III and IV), the 5-year survival rate for early stage (60%; 95%CI: 0.51-0.67), was higher than for late stage (27%; 95%CI: 0.19-0.34) with high statistical significance (p<0.001). The hazard ratio of patients with stage IV was 11.6 times greater than for stage I (p=0.03). The findings indicate that the different stages of breast cancer markedly effect the overall survival rate.