Supraclavicular lymph node dissection with radiotherapy versus radiotherapy alone for operable breast cancer with synchronous ipsilateral supraclavicular lymph node metastases: a real-world cohort study

Background: The role of supraclavicular lymph node dissection (SCLD) in the treatment of breast cancer with ipsilateral supraclavicular lymph node metastasis (ISLM) remains controversial. We evaluated the role of SCLD in the treatment of breast cancer with ISLM and identified patients who may benefit from SCLD. Methods: Data on patients presenting with breast cancer to the Breast Disease Center, Southwest Hospital, The Army Medical University from January 2004 and December 2017 were retrospectively screened. The median duration of follow-up was 36 months (2-175 months). 305 patients who were recently diagnosed with ISLM were eligible for the analysis. Results: Overall, 9,236 women presented with breast cancer during the study period. Among the patients included, 146 and 159 received SCLD with radiotherapy (RT) and RT alone, respectively. Synchronous ISLM without distant metastases were present in 3.6% cases. The 3- and 5-year overall survival (OS) and disease-free survival (DFS) rates were 79.5% and 73.9%, respectively, and 67.5% and 54.8%, respectively. However, SCLD with RT was not associated with superior survival on both univariate and multivariate analyses. On stratified analyses, patients with non-luminal A tumors with 4-9 positive axillary lymph nodes who underwent SCLD with RT had both superior OS (HR =5.296; 95% CI: 1.857-15.107; P=0.001) and DFS (HR =5.331; 95% CI: 2.348-12.108; P<0.001) compared with those who received RT alone. Conclusions: SCLD may not beneficial in improving survival for unselected breast cancer patients with ISLNM. There is less of a tendency to perform SCLD in the luminal A group.