Multivariate analysis using a Cox proportional hazards model was performed to assess the prognostic value for MFS of the parameters found to be significant in univariate analysis (i.e., SBR histological grade, lymph node status, macroscopic tumor size, PR status [Additional file 2: Table S1] and combined MMP13 and ETV4 mRNA levels). The gene discussed is ETV4; the disease is neoplasm.