Breast cancer patients with four or more lymph node metastases generally show poor prognosis. However, some can survive for a long period. In this study, we retrospectively evaluated these cases for estrogen receptor status and cell proliferation potential in an attempt to predict patient outcome more accurately. Ninety-two radically operated primary breast cancer patients with four or more lymph node metastases were examined. High PCNA LI and ER-negative status were significantly associated with poor outcome. Then, survival analysis was performed on combination of ER and PCNA LI status, remarkable difference was shown in the prognosis of the patients.