Although increased β2-M serum levels in patients with breast cancer have been previously reported [6, 9, 12], the clinical value of β2-M as a prognostic factor and predictor of survival, and its mechanism in patients with breast cancer, need further study, since breast cancer has different molecular subtypes [14] and patients with the same clinical stages and pathological types of breast cancer, treated with same scheme, have different therapeutic and prognostic effects. This evidence concerns the gene B2M and breast carcinoma.