The Significance On Neoadjuvant Anthracycline-based Chemotherapy Response To Outcome Among Breast Cancer Subtypes By Immunohistochemistry

Objective:we have identified four major subtypes of breast cancer(luminal A,luminal B, Her-2+/ER-,basal-like) according to ER, PR, Her-2 status and examined the relationship of neoadjuvant anthracycline-based chemotherapy response to outcome among these breast cancer subtypes by Immunohistochemistry.Methods:we retrospectively analysis 390 patients with stage II and III breast cancer who received neoadjuvant chemotherapy (CAF or CEF) for at least two cycles from Janu 2002 to Dece 2008. Follow-up data were available. Immunohistochemistry have identified four major subtypes of breast cancer: luminal A,luminal B,Her-2+/ER-,basal-like.The relationship of neoadjuvant anthracycline-based chemotherapy response to outcome among these breast cancer subtypes were analyzed.Results:1,Among all 390 cases, Luminal A was the majority (42.3%) and the least were Luminal B (13.3%) and Her-2+/ER-(20.0%),basal-like (24.4%) was more than Luminal B and Her-2+/ER-. All patients received Surgery following neoadjuvant chemotherapy,and adjuvant endocrine therapy was given to Luminal A and Luminal B. The molecular subtypes were not different in age, menopausal status, pathological type, clinical stage and histological grade. 2,Clinical response to CAF and CEF differed significantly among the subtypes(P<0.05),with Her-2+/ER- and basal-like subtypes showing higher clinical response rates than luminal subtypes.3,The median follow-up time for the survivors in this cohort was 62 months. The Kaplan-Meier method was used to estimate time-to-event functions.It showed DFS,DDFS and OS were the highest for luminal A and were poor for Her-2+/ER- subtype and basal-like subtype,with statistically significant difference(Log-Rank test,P<0.05)Conclusion:1,Molecular subtypes are good predictors for response to neoadjuva-nt chemotherapy and play a role in judging prognosis of breast cancer.Compared with luminal tumors, Her-2+/ER- and basal-like subtypes of breast cancer are more sensitive to neoadjuvant anthracycline-based chemotherapy.2,It is simple and practicable By immunohistochemistry ER, PR and Her-2 to approximate molecular typing. Immunohistochemistry is easy to practice and more widely used in clinical.