PARASTERNAL METASTASIS AS PROGNOSTIC FACTOR OF BREAST CANCER

Although the presence of axillary lymph node (Ax) metastasis is currently the most important prognostic factor of breast cancer, the significance of parasternal lymph node (Ps) involvement as the prognostic factor has been still unknown. The paper deals with the significance of Ps metastasis as prognostic factor. Subjects were 267 cases of breast cancer undergone lymph node dissection including Ps. Methods of the investigation included a comparison of survival rates by numbers of positive Ps and a multivariate analysis (Cox model) using Ax metastasis, tumor diameter, histological differentiation lymphatic invasion, ER and protein expression of p53 or c-erbB2 as descriptive variables to speculate the contribution of Ps metastasis to the prognosis. When the survival rates were compared by dividing the subjects into three groups by the number of positive Ps, none, one, and more than two, there was a significant difference (p<0.01) among these three groups in an order of Ps_??_2, Ps=1 and Ps=0. Another study of comparing the survival rates by the number of positive Ps (Ps=0 versus Ps_??_1) after the subjects were divided into three groups by the number of positive Ax, none, 1 to 3, and more than 4, resulted in a significantly higher survival rate in Ps=0 group than Ps_??_1 group. In the multivariate analysis, Ps metastasis was the most prominent prognostic factor. It is concluded that to know the presence of Ps metastasis in breast cancer is useful in estimating the prognosis and determining therapeutic plan for adjuvant chemotherapy.