Postoperative CMF Does Not Ameliorate Poor Outcomes in Women With Residual Invasive Breast Cancer After Neoadjuvant Epirubicin/Docetaxel Chemotherapy.

Background: Neoadjuvant chemotherapy (NACT) is an accepted treatment approach in early-stage breast cancer. In contrast, the potential role of postneoadjuvant chemotherapy after taxane-containing NACT remains unclear. The aim of this study was to evaluate postneoadjuvant chemotherapy and further prognostic factors that predict outcome in women without pathologic complete remission (pCR).

Patients And Methods: A total of 377 patients with breast cancer who received preoperative chemotherapy were included in this retrospective study. Patients without standard NACT (6 cycles of epirubicin with docetaxel) or primary metastatic breast cancer and locally advanced, inoperable cancer were excluded from further analysis (n = 186). This resulted in a study population of 191 women (30 [15.7%] with pCR; 161 [84.3%] without pCR). Major outcome parameters were event-free survival (EFS) and overall survival (OS). The following parameters were tested for their prognostic role: postneoadjuvant chemotherapy, patient age, breast cancer subtype (luminal/HER2-negative tumors, HER2-positive tumors, and triple-negative tumors), histological grade, pCR, residual lymph node invasion, and residual invasive tumor size.

Results: At a median follow-up of 54 months, 51 disease relapses (26.7%) and 21 deaths (11%) were observed. In a comparison of patients with pCR with those without, no significant differences in EFS or OS were observed. Postneoadjuvant chemotherapy was significantly associated with shorter OS in patients without pCR.

Conclusion: In this population, which included a high percentage of patients with luminal cancers, pCR did not predict for improved OS. Postneoadjuvant chemotherapy showed no discernible benefit even in subgroups with aggressive tumor biology or significant remaining tumor burden. The use of such treatment should therefore be discouraged outside of clinical trials.