Histologic Grade and CD44 Are Independent Predictors of Axillary Lymph Node Invasion in Early (T1) Breast Cancer

Abstract

Background: The detection rate of small, often subclinical breast cancers is increasing in affluent societies. Concomitantly, the demand for more conservative surgical approaches is also increasing among the women affected. Predictors of the absence of nodal invasion would spare many patients with early breast cancer the risks, costs and side effects of lymphadenectomy, and thus treatment with curative intent would be applied using really minimal surgery. Patients and Methods: We reviewed the records of 135 patients with unifocal invasive breast cancers, 2 cm or less in diameter, operated upon at ‘Fundación Tejerina-Centro de Patología de la Mama’, Madrid, Spain, between January 1993 and December 1997. Full clinical and pathological data were available for all of them, together with estrogen and progesterone receptor determinations, which had been routinely performed in 134 and 133 cases, respectively. Additionally, Ki67, c-erb-B2, p53, nm23, HSP27, HSP60 and CD44std expression was studied on archival, paraffin-embedded tumor material from these same patients by means of immunohistochemistry. Results: In the univariate analysis, only histologic grade 3 (p < 0.001), Ki67 expression in more than 10% of tumor cells (p = 0.005) and CD44std negativity (p = 0.004) were significantly associated with axillary node involvement. In multivariate analysis, histologic grade 3 and CD44std negativity retained statistical significance, and thus emerged as independent predictors of nodal invasion. The combination of both, furthermore, identified a subgroup in which the axillary nodes were invariably affected. Conclusion: Some pathological and molecular features of small breast cancers were able to predict nodal metastasis significantly. However, none, either alone nor combined, was able to exclude axillary node invasion completely.