Identification of breast cancer patients with high risk of early recurrence after radical mastectomy. II. Clinical and pathological correlations. A report of the Primary Therapy of Breast Cancer Study Group.

A prospective study of factors that might be helpful in predicting recurrence of breast cancer during the 2 years after radical mastectomy has been completed in 381 women by the Cooperative Breast Cancer Group (National Cancer Institute). Identification of clinical factors which might be associated with such recurrence has been achieved. A multivariate analysis of the data was oriented toward the identification of clinical factors other than lymph node status that might be simultaneously used to predict recurrence because of the current trend of cancer therapy toward more limited surgery. Degree of differentiation of the tumor, blood vessel invasion, patient age and tumor size were identified as important predictors of recurrence for premenopausal patients and tumor size was identified as important for postmenopausal patients. The addition of axillary lymph node status to these factors, however, made a significant improvement in the prediction equation for both pre- and postmenopausal patients. Studies of this type are of particular value to understand further the biology of breast cancer which is necessary to develop rational primary and adjuvant treatment strategies.