Comparison of supraclavicular surgery plus radiotherapy versus radiotherapy alone in breast cancer patients with synchronous ipsilateral supraclavicular lymph node metastasis: A multicenter retrospective study.

PURPOSE:To evaluate and compare the outcomes of supraclavicular lymph node dissection plus radiotherapy (RT) and RT alone for patients with synchronous ipsilateral supraclavicular lymph node metastasis. METHODS:In all, 293 patients with synchronous ipsilateral supraclavicular lymph node metastasis across three centers were included. Of these, 85 (29.0%) received supraclavicular lymph node dissection plus RT (Surgery + RT) and 208 (71.0%) received RT alone. All patients received preoperative systemic therapy followed by mastectomy or lumpectomy and axillary dissection. Supraclavicular recurrence-free survival (SCRFS), locoregional recurrence-free survival (LRRFS), distant metastasis-free survival (DMFS), disease-free survival (DFS), and overall survival (OS) were evaluated by using the Kaplan-Meier method and multivariate Cox models. Multiple imputation was used for missing data. RESULTS:The median follow-up duration of the RT and Surgery + RT groups were 53.7 and 63.5 months, respectively. For the RT and Surgery + RT groups, the 5-year SCRFS rates were 91.7% vs. 85.5% (P = 0.522), LRRFS rates were 79.1% vs. 73.1% (P = 0.412), DMFS rates were 60.4 vs. 58.8% (P = 0.708), DFS rates were 57.6% vs. 49.7% (P = 0.291), and OS rates were 71.9% vs. 62.2% (P = 0.272), respectively. There was no significant effect on any outcome when comparing Surgery + RT versus RT alone in the multivariate analysis. Based on four risk factors of DFS, patients were classified into three risk groups: the intermediate- and high-risk groups had significantly lower survival outcomes than the low-risk group. Surgery + RT did not improve outcomes of any risk group compared with RT alone. CONCLUSIONS:Patients with synchronous ipsilateral supraclavicular lymph node metastasis may not benefit from supraclavicular lymph node dissection. Distant metastasis remained the major failure pattern, especially for intermediate- and high-risk groups.