A retrospective study of metachronous and synchronous ipsilateral supraclavicular lymph node metastases in breast cancer patients

Clinically, ipsilateral supraclavicular lymph node metastasis (ISLM) in breast cancer can be classified into 2 manifestations: metachronous and synchronous. Synchronous ISLM (T1-4, N3, M0) is stage IIIc. Metachronous ISLM is isolated supraclavicular lymph node relapse after curative treatment. Although both are featured with ipsilateral supraclavicular lymph node metastases they are two clinical entities needing to be addressed differently. It is of particular interest to know other potential discrepancies between them except for the timing of ISLM occurrence. We retrospectively reviewed 2486 breast cancer patients. Among them, 48 women were identified with metachronous ISLM and 33 with synchronous ISLM. No significant difference was found between them in terms of clinicopathological characteristics as well as survival. However, the multivariate analysis showed they had different independent prognostic factors. Axillary lymph node metastasis status (P = 0.009) and chemotherapy after occurrence of ISLM (P = 0.016) were independent prognostic predictors for metachronous ISLM whilst primary tumor size (P = 0.016) and radiotherapy after diagnosis of ISLM (P = 0.022) were independent prognostic factors for synchronous ISLM. The multidisciplinary management of ISLM patients is strongly recommended.