Predictors of 4 or more positive axillary nodes in patients with node-positive T1-2 breast carcinoma: The indications for adjuvant irradiation of the level III axilla and supraclavicular fossa

Purpose: We evaluate the predictors of 4 or more involved axillary nodes in patients with node-positive T1-2 breast carcinoma to select a group of patients who are indicated for adjuvant irradiation of the level III axilla and supraclavicular fossa (SCF). Methods: We analyzed 286 patients with positive axillary nodes and who were without distant metastases and who underwent breast conserving surgery and axillary lymph node dissection or modified radical mastectomy. We investigated the relationship between the patients and the tumor factors and 4 or more positive axillary nodes. Results: On the multivariate logistic-regression analysis, an increased tumor size (p=0.002), the presence of lymphovascular space invasion (LVSI) (p<0.001) and a palpable mass p<0.001) were positively associated with involvement of 4 or more axillary lymph nodes. In our study, 86.1% of the patients with all the unfavorable factors had involvement of 4 or more nodal metastases. Conclusion: Our data suggest that for patients with node-positive T1-2 breast cancer, the presence of 4 or more involved nodes is frequently observed for the patients with an increased tumor size, the presence of LVSI and a palpable mass at the time of diagnosis, and we recommend that they undergo irradiation of the high axilla and SCF for adjuvant care, if they do not undergo complete axillary dissection.