The role of radical axillary dissection in breast cancer management is presently under discussion. In this study we have evaluated the relationship between the pattern of metastatic axillary lymph node involvement by level and some of the main prognostic factors (age of the patient, size, grading, estrogen receptor and progesterone receptor status of the primary tumor) in 185 patients with operable breast cancer. The III level appeared to be involved in 31 (16.8%) out the 108 patients with axillary lymph nodes positive for metastases. A discontinuous pattern of axillary involvement (skip metastases) was observed in about 10% of cases. Logistic regression analysis of the data shows that only G3 is significantly correlated with the risk of III level invasion (p less than 0.05). We conclude that, at present, a selection of possible candidates for a less than radical axillary dissection is not as yet feasible. Since the risk for III level invasion cannot be sufficiently defined.