Purpose: Supraclavicular lymph node metastasis in breast cancer patients has a poor prognosis, and aggressive local treatment has usually resulted in severe morbidity. The purpose of this study was to select high-risk neck metastasis patients for prophylactic radiotherapy.
Methods: Between 1990 and 1998, 2658 consecutive invasive breast cancer patients underwent surgery and adjuvant therapy in the hospital. The median age was 47 years (range 22-92). The median follow-up period was 39 months. The following factors were analyzed: age, tumor size, tumor location, histologic type, histologic grade, estrogen and progesterone receptor status, DNA flow cytometry study results, number of positive axillary lymph nodes, use of chemotherapy, radiotherapy, and/or hormonal therapy, and level of involved axillary nodes.
Results: Of the 2658 patients, 113 (4.3%) developed supraclavicular lymph node metastasis during this period. Young age (< or =40 years), tumor size >3 cm, high histologic grade, angiolymphatic invasion, negative estrogen receptor status, synthetic phase fraction >4%, >4 positive nodes, and level II or III involved nodes were all significant for predicting neck metastasis in the univariate analysis. Three predictive factors were significant after multivariate analysis: high histologic grade, >4 positive nodes, and axillary level II or III involved nodes. In patients with axillary level I involved nodes and < or =4 positive nodes, the incidence was 4.4%. If axillary level III was involved, the rate of supraclavicular lymph node metastasis was 15.1%.
Conclusion: The incidence of supraclavicular lymph node metastasis was higher in the groups with >4 positive nodes and in those with axillary level II or III involved nodes. Selective use of comprehensive radiotherapy for these high-risk patients will achieve good locoregional control.