Neoadjuvant treatment with trastuzumab in HER2-positive breast cancer: results from the GeparQuattro study.

PURPOSE Trastuzumab, a humanized antibody against the human epidermal growth factor receptor type 2 (HER2), has shown high efficacy in breast cancer. We prospectively investigated its efficacy given simultaneously with anthracycline-taxane-based neoadjuvant chemotherapy. PATIENTS AND METHODS Patients with operable or locally advanced, HER2-positive tumors were treated preoperatively with four cycles of epirubicin/cyclophosphamide followed by four cycles of docetaxel with or without capecitabine (EC-T[X]) and trastuzumab 6 mg/kg (with a loading dose of 8 mg/kg) every 3 weeks during all chemotherapy cycles. Patients with HER2-negative tumors treated in the same study with the same chemotherapy but without trastuzumab were used as a reference group. Results Of 1,509 participants, 445 had HER2-positive tumors treated with trastuzumab and chemotherapy. Pathologic complete response (pCR; defined as no invasive or in situ residual tumors in the breast) rate was 31.7%, which was 16% higher than that in the reference group (15.7%). HER2-positive patients without response to the first four cycles of EC showed an unexpectedly high pCR rate of 16.6% (3.3% in the reference group). Breast conservation rate was 63.1% and comparable to that of the reference group (64.7%). EC-T(X) plus trastuzumab was associated with more febrile neutropenia and conjunctivitis, but with a comparable short-term cardiac toxicity profile as the reference group. CONCLUSION This trial confirms that combining trastuzumab with anthracycline-taxane-based neoadjuvant chemotherapy results in a high pCR rate without clinically relevant early toxicity. Combination of chemotherapy with trastuzumab should be considered when neoadjuvant treatment is given to patients with HER2-positive breast cancer.

Capecitabine in addition to anthracycline- and taxane-based neoadjuvant treatment in patients with primary breast cancer: phase III GeparQuattro study.

PURPOSE Capecitabine can be integrated either concomitantly or sequentially to anthracycline-plus-taxane-based regimens. PATIENTS AND METHODS Patients with large operable or locally advanced tumors, with hormone receptor-negative tumors, or with receptor-positive tumors but also clinically node-positive disease were recruited to receive preoperatively four cycles of epirubicin plus cyclophosphamide (EC; epirubicin 90 mg/m(2) and cyclophosphamide 600 mg/m(2)). Patients were then randomly assigned to four cycles of docetaxel (100 mg/m(2)), four cycles of docetaxel + capecitabine (TX; docetaxel 75 mg/m(2) plus capecitabine 1,800 mg/m(2)), or four cycles of docetaxel (75 mg/m(2)) followed by four cycles of capecitabine (1,800 mg/m(2); T-X). Patients with human epidermal growth factor receptor 2 (HER-2) -positive tumors received trastuzumab concomitantly with all cycles. Primary objectives were to assess the effect of docetaxel by comparing EC plus docetaxel versus EC plus TX and to assess the effect of duration by comparing EC plus TX versus EC plus T-X on pathologic complete response (pCR, without invasive/noninvasive breast tumor, regardless of nodal status) at surgery, irrespective of trastuzumab treatment. Results Of 1,509 patients starting EC, 1,421 were randomly assigned to docetaxel (n = 471), TX (n = 471), or T-X (n = 479). At surgery, pCR rates were 22.3%, 19.5%, and 22.3%, respectively; the difference for docetaxel (EC plus docetaxel v EC plus TX) was 2.8% (95% CI, -2.4% to 8.0%; P = .298).The difference for duration was -2.8% (95% CI, -8.0% to 2.4%; P = .298). Breast conservation rates were 70.1%, 68.4%, and 65.3%, respectively (P = .781 for docetaxel; P = .270 for duration). Concomitant but not sequential treatment with docetaxel was associated with more diarrhea; nail changes, and hand-foot-syndrome, but it was associated with less edema. CONCLUSION Adding capecitabine to or prolonging duration of neoadjuvant EC plus docetaxel does not result in higher efficacy at surgery.