Analysis of Postoperative Survival and Prognostic Factors in Breast Cancer

Kim, Jee Soo; Noh, Dong Young; Yoon, Yeo Kyu; Oh, Seung Keun; Choe, Kuk Jin

Abstract

We reviewed 723 breast cancer patients treated between Jan. 1981 and Dec. 1991 at the Department of Surgery, Seoul National University Hospital. Survival curves were constructed using the life table method. The significance of the differences in the survival patterns was determined by the log-rank test in univariate analysis, by the Cox proportional hazards regression test in multivariate analysis. Distribution of the patients and the survival rate between this patients and 802 breast cancer patients from Jan. 1970 to Dec. 1988 were compared using paired sample t-test. The mean age of the patients was 46.9 years, and the most prevalent age group was the 5th decade. The distribution of patients according to the tumor stage showed no meaningful change from our previous study. The overall 5-year and 10-year survival rate were 80.1%, 68.4% respectively. On univariate analysis, tumor size, lymph node status, number of lymph node metastasis and stage were found to influence survival significantly. On multivariate analysis, tumor size(p=0.0004), lymph node status (p=0.0231) were found to be significant prognostic factors. In conclusion, the increased proportion of early stage breast cancer patients, although not statistically significant, seems to account for the slight improvement of the overall survival compared to that of our previous study. The tumor size and the lymph node status were potential prognostic factors on survival, a result which is as that of our previous study.