Long-term outcome and pattern of relapse after neoadjuvant chemotherapy in patients with human epidermal growth factor receptor 2-positive primary breast cancer.

OBJECTIVE

Determinants of long-term outcome of patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer who received neoadjuvant chemotherapy (NAC) are not clear. The purpose of this study was to explore the prognostic factors of HER2-positive breast cancer patients administered NAC.

METHODS

A retrospective analysis of 125 HER2-positive breast cancer patients treated by NAC using an anthracycline plus taxane with (HCN group, n = 54) or without trastuzumab (non-HCN group, n = 71) was performed. The clinical parameters, including the pathological complete remission (pCR) rate, disease-free survival (DFS) and organ-specific recurrence-free survival, were measured.

RESULTS

According to the results of the univariate analyses, age, clinical stage, pCR and axillary lymph node status were the factors significantly associated with the DFS. The inclusion of trastuzumab in the NAC regimen did not yield a significant difference in the DFS. Only the axillary lymph node status and age were found to be the significant factors affecting the DFS in a multivariate model. There were no significant differences in the patient/tumor characteristics between the HCN and non-HCN groups except for the pCR rate (50% in the HCN group vs. 24% in the non-HCN group) and the median follow-up time (738 days in the HCN group vs. 1579 days in the non-HCN group). Within the first 2 years from the initiation of NAC treatment, the central nervous system (CNS) was the most common site of first recurrence in the HCN group, whereas no cases of CNS metastasis were observed in the non-HCN group.

CONCLUSIONS

The pathological axillary node status and age were found to be the significant prognostic factors in HER2-positive breast cancer patients who received NAC. The pattern of recurrence may be different between HCN-treated and non-HCN-treated patients.