Background: Patients with supraclavicular metastases at diagnosis of breast cancer were classified between 1987 and 2002 as having stage M(1) breast cancer according to the tumor-node-metastasis (TNM) system. The 2003 edition of the TNM staging guidelines has classified such patients as having stage IIIC disease. To determine relative prognosis, we compared long-term survival in a population-based cohort of patients with isolated supraclavicular metastases (nodal-M(1)) to outcomes of patients with stage IIIB or M(1) (other) disease at presentation.
Materials and methods: Among patients with breast cancer and known tumor stage referred to the British Columbia Cancer Agency from 1976 to 1985, 336 IIIB, 233 M(1), and 51 nodal-M(1) patients were identified. Actuarial overall and breast cancer-specific survival rates were determined to 20 years.
Results: Overall survival at 20 years was 13.2% for nodal-M(1) cases (95% confidence interval [CI], 5% to 26%), 9.4% for IIIB cases (95% CI, 6% to 14%), and 1.3% for M(1) (other) cases (95% CI, 0.4% to 3.5%; log-rank P <.0005). Overall survival was similar between nodal-M(1) and IIIB cases (P =.27). Breast cancer-specific survival at 20 years was 24.1% for nodal-M(1) cases (95% CI, 13% to 37%), 30.2% for IIIB cases (95% CI, 23% to 38%), and 3.9% for M(1) (other) cases (95% CI, 2% to 8%; log-rank P <.0005). Breast cancer-specific survival was significantly different for nodal-M(1) cases compared with either IIIB or M(1) (other) cases (P =.008 for both).
Conclusion: Patients with supraclavicular metastases at diagnosis have significantly better outcomes than patients with M(1) (other) disease and overall survival similar to patients with IIIB disease. Reclassification as stage IIIC is appropriate for patients with breast cancer who present with supraclavicular nodal metastases alone.