Clinical behavior of untreated axillary nodes after local treatment for primary breast cancer

Background: The purpose of this study was to examine the rate of axillary failure in patients with primary breast cancer treated without axillary dissection or radiation and to determine what factors may be associated with axillary failure. Methods: We studied 112 patients with invasive breast cancer treated for primary disease with breast-conserving surgery without axillary dissection or radiation to the breast or axilla, accrued between 1977 and 1986, Data for these patients were prospectively gathered for a research database and reviewed retrospectively to determine axillary failure. The effects of age, tumor size, estrogen receptor (ER) status, progesterone receptor (PgR) status, histologic grade, nuclear grade, and tumor emboli on time to axillary failure were examined. Results: The median follow-up was 9.6 years. There were 26 axillary recurrences, resulting in a 10-year actuarial nodal control rate of 72%. Patients with nodal failure proceeded to axillary dissection with minimal morbidity. In both univariate and multivariate analyses, only tumor size was significantly associated with axillary failure (p = 0.04 and p = 0.06, respectively). Conclusions: This study demonstrates a significant effect of tumor size on axillary failure and a reasonable rate of local control in small tumors. Further research should examine the utility of axillary dissection in women with small breast cancers.