T3 disease at presentation or pathologic involvement of four or more lymph nodes predict for locoregional recurrence in stage II breast cancer treated with neoadjuvant chemotherapy and mastectomy without radiotherapy

Abstract

Purpose: To help define the clinical and pathologic predictors of locoregional recurrence (LRR) in breast cancer patients treated with neoadjuvant chemotherapy and mastectomy without radiotherapy for early-stage disease. Methods and Materials: We retrospectively reviewed the outcomes of all 132 patients with Stage I or II breast cancer treated in prospective institutional trials with neoadjuvant chemotherapy and mastectomy without radiotherapy between 1974 and 2001. The clinical stage (American Joint Committee on Cancer 1988) at diagnosis was I in 5%, IIA in 46%, and IIB in 49% of patients. The median age at diagnosis was 49 years. All patients were treated with either a doxorubicin-based neoadjuvant regimen or single-agent paclitaxel. The total LRR rates were calculated by the Kaplan-Meier method, and comparisons were made with two-sided log–rank tests. The median follow-up was 46 months. Results: The actuarial LRR rate at both 5 and 10 years was 10%. Factors that correlated positively with LRR included clinical Stage T3N0 ( p = 0.0057), four or more positive lymph nodes at surgery ( p = 0.0001), age ≤40 years at diagnosis ( p = 0.0001), and no use of tamoxifen. In the patients who did not receive tamoxifen, estrogen receptor-positive disease correlated positively with LRR ( p = 0.0067). The 5-year LRR rate for the 42 patients with clinical Stage T1 or T2 disease and one to three positive lymph nodes at surgery was 5% (only two events). Conclusion: For patients with clinical Stage II breast cancer, T3 primary disease, four or more positive lymph nodes after chemotherapy, and age ≤40 years old predicted for LRR. For most patients with clinical T1 or T2 disease and one to three positive lymph nodes, the 5-year risk for LRR was low, and the routine inclusion of postmastectomy radiotherapy does not appear to be justified.