Pathological complete response as a surrogate for relapse-free survival in patients with triple negative breast cancer after neoadjuvant chemotherapy.

We retrospective analyzed triple negative breast cancer (TNBC) patients who received either taxane-based or anthracycline-based neoadjuvant chemotherapy, evaluated whether pathological complete response (pCR) is a surrogate endpoint for relapse free survival (RFS) in TNBC and explored which subgroup of patients benefits more from superior treatment regimen. 186 patients received taxane-based (Group A) or anthracycline-based (Group B) neoadjuvant chemotherapy, median follow-up was 48.1 months. 42 patients received total pCR (ypT0/is ypN0), 34 in Group A and 8 in Group B, p < 0.001. Patients who achieved pCR had an increased RFS when compared with non-pCR patients, p = 0.043. Patients in Group A had a better RFS, p = 0.025, after adjusting for tumor size and clinical lymph node status before neoadjuvant therapy. Only patients sensitive to neoadjuvant chemotherapy exhibited RFS benefit from taxane-based treatment, and those who were treatment insensitive had similar RFS between both groups. Our analysis showed Taxane-based regimen had higher pCR rate and could predict improved RFS in TNBC, and the prognostic value was greater in treatment sensitive patients. This retrospective analysis supports the use of pCR as a surrogate endpoint for RFS in TNBC.