Effect of Adjuvant Chemotherapy of Operable Breast Cancer : Survival and Prognostic Factor Analysis

Kim, Jeong Gyun; Kim, Tae Won; Lee, Je Hwan; Kim, Sung Bae; Suh, Cheolwon; Lee, Kyoo Hyung; Lee, Jung Shin; Ahn, Sei Hyun; Chang, Hyesook; Kim, Sang Hee; Kim, Woo Kun

Abstract

PURPOSE: Though the therapy using regimens similar to western countries has been done by medical oncologists in several different centers in Korea, there is no large scale study about the results of those adjuvant chemotherapy as in western country and it is not clear whether the results are same in Korean population as in western countries not only in overall outcome but also depending on various prognostic categories. It is important to review whether Korean patients would have equivalent results as in western countries or not when they were treated with the same standardized regimens. We examined the effect of adjuvant systemic chemotherapy on survival and analyzed prognostic factors.
MATERIALS AND METHODS
A retrospective analysis of survival and prognostic factors was done in 341 consecutive breast cancer patients who received curative operation followed by systemic conventional adjuvant chemotherapy between 1989 and 1996. The survival rate was compared using Kaplan-Meier method and Log-rank method. To evaluate an independent prognostic factors, Cox proportional hazard model was used.
RESULTS
After median follow up of 56 months (range 28 118 months), the mean disease-free survival (DFS) and overall survival (OS) was 81.0+/-2.7 and 91.5+/-2.6 months respectively. The 5-year DFS and OS rate was 61% and 77%, respectively. On univariate analysis, prognostic factors significant for DFS were tumor size (<2 cm vs. > 2 cm), hormonal receptor status, and histologic grade. Prognostic factors affecting both DFS and OS are as follows: age ((pound)40 vs 41-50 vs. (3)51), number of axillary node involvement, .and stage. Multivariate analysis showed that the number of axillary node involvement was the strongest adverse predictor.
CONCLUSION
The effect of adjuvant chemotherapy in Korean patients is not different from western countries and this report emphasizes the prognostic importance of number of axillary node involvement in breast cancer patients and necessity of intensive management of those with four or more positive nodes.