When plotted according to the Kaplan-Meier method with significance determined using the log-rank test, the expression of calpastatin, calpain-1 and calpain-2 in the core biopsies was not associated with breast cancer specific survival in the total patient cohort (P=0.470, P=0.790, P=0.174 respectively). This evidence concerns the gene CAPN1 and breast cancer.