Purpose: To analyze tumor control and survival for breast cancer patients with 10 or more positive lymph nodes without systemic disease, treated by adjuvant radiation alone or combined-modality therapy.
Methods and materials: We reviewed the records of 309 consecutive patients with these characteristics who received locoregional radiotherapy (RT) at our institution. The majority of patients had clinical Stage II or IIIA-B disease (43% and 48%, respectively). The median number of positive axillary lymph nodes was 15 (range, 10-78). Adjuvant therapy consisted of RT alone, with or without chemotherapy, tamoxifen, and/or ovarian castration.
Results: The overall 5-year and 10-year disease-free survival (DFS) rates were 20% and 7%, respectively. Median DFS was higher for patients with Stage I-II compared with those with Stage IIIABC (28 vs. 19 months; p = 0.006). Median DFS for patients aged <or=35 years was lower than that of older patients (12 vs. 24 months; p < 0.0001). Patients treated with a combination therapy had a higher 5-year DFS rate compared with those treated by RT alone (26% vs. 11%; p = 0.03). In multivariate analysis, clinical stage (III vs. I, II; relative risk = 1.8, p = 0.002) and age (<or=35 vs. others; relative risk = 2.6, p <0.001) were found to be independent variables for DFS.
Conclusion: This retrospective data analysis identified young age and advanced clinical stage as pertinent and independent clinical prognostic factors for breast cancer patients with advanced axillary disease (10 or more involved nodes). These factors can be used for further prognostic classification.