MET expression is associated with disease-specific survival in breast cancer patients in the neoadjuvant setting

MET and RON receptor tyrosine kinases play an important role in tumor progression. The aim of this study was to determine the predictive or prognostic impact of MET and RON in breast cancer patients treated with neoadjuvant chemotherapy (NAC). Immunohistochemical analyses were performed to retrospectively examine the predictive or prognostic impact of MET and RON expression in 129 breast cancer patients treated with NAC followed by definitive surgical resection. MET-positive tumors were detected in 89 patients (68.9%) and RON-positive tumors in 94 patients (72.9%). Survival analysis showed that MET expression was correlated with longer disease-specific survival (DSS; P=0.016), whereas RON expression was not associated with survival rates. MET expression was a significant factor for DSS in the non-pCR group in subgroup analysis (P=0.024) and a marginal significant independent prognostic factor for DSS in multivariate analysis. The MET-positive group had higher pCR than the MET-negative group but the difference was not statistically significant (P=0.266). MET expression is a prognostic factor for DSS in breast cancer patients receiving NAC and may provide additional prognostic information in patients not achieving a pCR.