[Two cases of breast cancer responding to primary systemic chemotherapy containing trastuzumab without surgery]

The first case was a 40-year-old woman who was referred to our hospital with a complaint of left breast tumor. She was diagnosed as invasive ductal carcinoma (T2N0M0, Stage IIA). The tumor was ER-negative, PR-negative and HER2-positive. After primary systemic chemotherapy with 6 courses of 5-fluorouracil+epirubicin+cyclophosphamide(FEC)and 3 courses of weekly paclitaxel (PTX)+trastuzumab, the efficacy of chemotherapy was judged as a complete response (CR). After chemotherapy, radiotherapy for her left breast was performed without surgery. At 21 months after CR, local efficacy was judged as CR, but liver and bone metastases appeared, and were treated by capecitabine and trastuzumab. The efficacy of chemotherapy was judged as a partial response (PR). The second case was a 26-year-old woman referred to our hospital with a complaint of right breast tumor. She was diagnosed as invasive lobular carcinoma (T2N0M0, Stage IIA). The tumor was ER-positive, PR-negative and HER2-positive. After primary systemic chemotherapy with 4 courses of FEC and 6 courses of docetaxel+trastuzumab, the efficacy of chemotherapy was judged as CR. Then, 4 courses of weekly PTX+trastuzumab were performed. After chemotherapy, radiotherapy for her right breast was performed without surgery. The efficacy of treatment was judged as CR for 15 months.