PhD Ta Van To Training institution: Hanoi Medical University New conclusions of the thesis: Evaluate histopathological response in surgical specimens according to response classification of Japanese Breast Cancer Society 2007, the results were: Grade 0, 1a, 1b, 2a, 2b, Grade 3 without carcinoma in situ and grade 3 with carcinoma in situ were respectively 20.4%; 14.8%; 17.6%; 12%; 7.4%; 23.2% and 4.6%.