Pathologic complete response after neoadjuvant chemotherapy is considered as a surrogate of survival by most authors, although there are special phenotypes, such HER2 positive, where their potential as apredictor of survival is stronger.
Overall survival was analyzed according to pathologic response in a cohort of early breast cancer patients (all subtypes) treated with standard neoadjuvant chemotherapy. Between March 2000 to October 2016, 459 breast cancer patients were treated with neoadjuvant chemotherapy with anthracicline and taxane regimens.
Median age was 52 (range 28-87), 173 tumors (38%) were classifyed as HER2 positive, 148 (32%) triple negative and 138 (30%) as luminal breast cancer. Median initial size was 34 mm (10-100) and 237 patients (51%) had initial node involvement. We achieved a total of 152/459 complete pathologic response with a 43% rate in HER2 positive, 44% in triple negative and 9% in luminal breast cancer patientes. Ten years disease free survival in the whole serie was 83%, with a 72% for patients without complete pathologic response versus 90% for complete pathologic response (long rang <0,00001). A strong correlation between pathologic response and survival wass found in all subtypes (long rang p:0,033; 0,028 and 0,027 in HER2 positive, luminal and triple negative respectively). A table with survival results according the RCB response by Symmans method in the whole series and different phenotypes is attached.
Phenotype RCB type 0 RCB1 type I RCB type II RCB type III Overall Median DFS:167 HR: 1 Median DFS:156 HR: 2,6 Median DFS:130 HR: 4,5 Median DFS:85 HR: 9,6 HER 2 positive Median DFS: 126 HR: 1 Median DFS: 90 HR: 1,6 Median DFS:100 HR: 2,5 Median DFS:96 HR: 4,4 Luminal Median DFS: 176 HR: 1 Median DFS: 160 HR: 2,8 Median DFS:115 HR: 4,8 Median DFS: NA HR: NA Triple negative Median DFS:188 HR: 1 Median DFS: 141 HR: 8,8 Median DFS: 117 HR: 16,7 Median DFS:122 HR: 28.4
Pathologic response is a strong predictor of overall survival in all breast cancer phenotypes althoug in the triple negative has the highest magnitude with a HR of 28,4 in patients with worse pathologic response (RCB type III). Neoadjuvant chemotherapy should be considered in the majority of patients who are candidates to chemotherapy, specially in triple negative and HER2 positive; however, in luminal phenotype a better selection for neoadyuvant chemotherapy is needed.
Hospital Universitari Arnau de Vilanova.
Has not received any funding.
All authors have declared no conflicts of interest.