Re-Examination of Tumor Material and Re-Evaluation of Patient Data From Patients Treated With Neo-adjuvant Therapy

This is a prospective examination of ribonucleic acid (RNA) extracted from tumor material of breast cancer patients treated with a neo-adjuvant therapy. The RNA will be analysed for expression of estrogen receptor (ER 1), progesterone receptor (PgR), HER2 and Ki-67 with MammaTyper™. According to the determined values for the individual parameters at least 4 subtypes can be distinguished to date * Luminal A-type * Luminal B-type * HER2-type * Triple-negative-type As non-clinical endpoint, the agreement of new subtyping with Immunohistochemical methods will be evaluated. As clinical objective, the 5 year Distant metastasis free survival (DMFS) and Overall survival (OS) will be reevaluated according to the new subtyping.