Concurrent administration of chemo-endocrine therapy for postmenopausal breast cancer patients

We have been treating hormone receptor-positive, postmenopausal women with breast cancer with a regimen of neoadjuvant chemotherapy (NAC), FEC (fluorouracil, epirubicin, and cyclophosphamide), followed by weekly doses of paclitaxel combined with the concurrent administration of anastrozole. In this article, we compared our results retrospectively with those of past trials.

Twenty-six patients that were postmenopausal and were younger than 70 years of age were selected. They all had primary operable tumors that were ≥2 cm in diameter (clinical T2-3, Nx, M0). All patients received four cycles of 500 mg/m² cyclophosphamide, 500 mg/m² 5-fluorouracil, and 80 mg/m² epirubicin (from April 2006, the dose was increased to 100 mg/m²) that were administrated on day 1 of every 3rd week and followed by 12 cycles of 80 mg/m² paclitaxel on day 1 of each week. From the beginning of NAC the aromatase inhibitor, anastrozole, was concomitantly administered at a dose of 1 mg/day. After surgery, the clinical and pathological responses were examined.

Among the 26 patients, 5 (17.9%) achieved clinical complete response, 16 (57.1%) clinical partial response, and 4 (14.3%) clinical stable disease. If the nodal status was counted, the pathological complete response (pCR) rate of our chemo-endocrine therapy was 11.5%.

The pCR rate of the concurrent administration of chemo-endocrine therapy was not lower than those of past trials, but it remains uncertain whether this positive result was due to the administration of the aromatase inhibiter or our NAC regimen. In order to answer this, we need to make a direct comparison between the concurrent versus sequential administration of the aromatase inhibitor during NAC in a prospective study.