Zhang L, Teng Y, Zhang Y, Liu J, Xu L, Qu J, Hou K, Yang X, Liu Y, Qu X. c‐Src expression is predictive of poor prognosis in breast cancer patients with bone metastasis but not in patients with visceral metastasis. APMIS 2012; 120: 549–57.

c‐Src expression is critical for breast cancer progression and it is particularly important for bone metastasis. In this study, we aimed to evaluate the effect of c‐Src on prognosis in metastatic breast cancer patients, and to conduct subgroup analysis to explore the role of c‐Src in bone metastasis and visceral metastasis respectively. We analyzed a total of 102 paraffin‐embedded primary tumor tissue sections from metastatic breast cancer patients using immunohistochemical staining for c‐Src, including 61 patients with bone metastases. Clinical data were collected retrospectively. We utilized survival analysis and the Cox proportional hazards model to explore the prognostic value of c‐Src expression in metastatic breast cancer. The c‐Src expression rate was 54.9% in the 102 metastatic breast cancer patients. Patients who exhibited c‐Src expression demonstrated poor progression‐free survival (PFS) (p = 0.044) and disease‐specific survival (DSS) (p = 0.017). Subgroup analysis demonstrated that c‐Src positive patients exhibited significantly worse bone metastasis‐free survival (p = 0.027) and DSS (p = 0.024), whereas in patients with non‐bone metastasis no significant difference was observed in PFS (p = 0.819) and DSS (p = 0.381). Multivariate analysis demonstrated that c‐Src expression was an independent predictor of DSS for patients with bone metastasis. Our findings demonstrate that c‐Src expression is a potential independent predictor of poor prognosis in breast cancer patients with bone metastasis.