Evaluation of pCR in neoadjuvant clinical trials of early stage breast cancer as surrogate endpoint for DFS and OS

The US Food and Drug Administration and the European Medicines Agency support the use of pathological complete response in neoadjuvant randomized clinical trials of early stage breast cancer as a surrogate end point for long-term clinical outcomes (disease-free survival and overall survival). Systematic review and meta-analysis of 54 neoadjuvant randomized clinical trials of early stage breast cancer (32,611 patients) found a lack of surrogacyof pathological complete response for both disease-free survival (R2=0.14; 95% CI 0.00-0.29) and overall survival (0.08; 0.00-0.22). The authors conclude that pCR should not be used as primary end point in regulatory neoadjuvant trials of early stage breast cancer.