Long-Term Outcomes of Breast Cancer Patients Who Underwent Selective Neck Dissection for Metachronous Isolated Supraclavicular Nodal Metastasis

SIMPLE SUMMARY: Very limited studies so far have analyzed the long-term oncologic outcomes of breast cancer patients that developed metachronous isolated supraclavicular nodal metastasis (miSLNM) with no available treatment strategy for the critical issue. The study enrolled 139 miSLNM patients; 61 patients underwent selective neck dissection. In median follow-up of 73.1 months, significantly better 5-year overall survival rate was found in the neck dissection group compared to the no-dissection group (68.9% vs. 57.7%, respectively; HR, 1.77 (1.22–2.55), p = 0.003). The findings suggest surgery for miSLNM should be integrated into multimodal therapy of miSLNM, and the restaging of miSLNM as rN3c rather than M1 disease if detected earlier. ABSTRACT: We retrospectively enrolled 139 patients who developed metachronous isolated supraclavicular lymph node metastasis (miSLNM) from 8129 consecutive patients who underwent primary surgery between 1990 and 2008 at a single medical center. The median age was 47 years. The median follow-up time from date of primary tumor surgery was 73.1 months, and the median time to the date of neck relapse was 43.9 months in this study. Sixty-one (43.9%) patients underwent selective neck dissection (SND). The 5-year distant metastasis-free survival (DMFS), post-recurrence survival, and overall survival (OS) rates in the SND group were 31.1%, 40.3%, and 68.9%, respectively, whereas those of the no-SND group were 9.7%, 32.9%, and 57.7%, respectively (p = 0.001). No SND and time interval from primary tumor surgery to neck relapse ≤24 months were the only significant risk factors in the multivariate analysis of DMFS (hazard ratio (HR), 1.77; 95% confidence interval (CI), 1.23–2.56; p = 0.002 and HR, 1.76, 95% CI, 1.23–2.52; p = 0.002, respectively) and OS (HR, 1.77; 95% CI, 1.22–2.55; p = 0.003 and HR, 3.54, 95% CI, 2.44–5.16; p < 0.0001, respectively). Multimodal therapy, including neck dissection, significantly improved the DMFS and OS of miSLNM. Survival improvement after miSLNM control by intensive surgical treatment suggests that miSLNM is not distant metastasis.