Comparison of neoadjuvant systemic treatment (chemotherapy with or without trastuzumab) responses with dynamic contrast-enhanced breast magnetic resonance imaging and histopathology in locally advanced breast cancer.

Abstract

e11507 Background: It is reported that dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) may have the potential of predicting response to neoadjuvant chemotherapy (NAC) for patients with breast cancer and it is more accurate than the other radiologic methods. We aimed to compare the responses to NAC ± trastuzumab with DCE-MRI and histopathologic findings in locally advanced breast cancer. Methods: Between January 2007 and October 2011, 38 female patients patients with locally advanced breast cancer who recieved NAC ± trastuzumab and had whole breast DCE-MRI before / after treatment and who also had surgery after treatment were included in our study. Patients received 4 cycles of antracyclin based and 4 cycles of taxane based chemotherapy protocols sequentially. 9 patients with HER-2 (+) breast cancer also received trastuzumab with taxane based chemotherapy. Before and after NAC ± trastuzumab, tumor measurements were evaluated by mammography (MG), ultrasound (US), DCE-MRI and compared with postoperative histopathologic findings. Response rates were assessed with RECIST (Response Evolution Criteria in Solid Tumors) 1,1 criteria. MRI were done with 1,5 Tesla MR ( Gyroscan Achieva Intera, Philips ). SPSS 15.0 and Kappa test were used for statistical analysis. Results: After NAC ± trastuzumab, breast DCE-MRI revealed 13.2% complete response (CR), 73.7% partial response (PR), 10.5% stabile disease (SD), and 2.6% progressive disease (PD) and 15.8% CR, 73.7% PR, 7.9% SD and 2.6% PD were shown with histopathology. After neoadjuvant systemic treatment, histopathologic and DCE-MRI responses revealed high positive correlation with kappa test (kappa: 0,63), but there were low correlation between not only histopathologic and MG responses but also US responses with kappa test (kappa: 0,2). Conclusions: DCE-MRI is more effective method than other radiologic methods for the evaluation of response to NAC ± trastuzumab when compared with the histopathologic findings.