A Phase II Study of Neoadjuvant Weekly Paclitaxel with and without Trastuzumab in Elderly Breast Cancer Patients

Abstract

Purpose: To evaluate the efficacy and safety of weekly paclitaxel with and without trastuzumab as neoadjuvant therapy for elderly stage II/III breast cancer patients. Method: Patients aged 65 years or older with stage II, IIIA, IIIB and estrogen receptoror progesterone receptor-negative breast cancer were included. Patients with HER2-negative tumors received paclitaxel 80 mg/m2 weekly for 12 doses. Patients with HER2-positive tumors received paclitaxel 80 mg/m2 and trastuzumab 4 mg/kg loading dose, followed by 2 mg/kg weekly for 12 doses. The primary endpoint is pathological complete response (CR) rate. Forty patients were planned to be enrolled. Results: This phase II study was discontinued due to slow accrual. Sixteen patients were enrolled from April 2003 to October 2005. The median age was 70.5 years and 15 patients (93.8%) were diagnosed as stage II disease. Nine patients (56.2%) had HER2-negative tumors and 7 (43.8%) had HER2-positive tumors. Only 7 patients (43.8%) completed chemotherapy as planned and a median of 10.5 cycles were given. The most reason for discontinuation of treatment was neurosensory toxicities. Eleven patients clinically responded (5 CR and 6 partial response) with a 68.8% total clinical response rate. The major toxicities were alopecia (68.8%) and neurosensory toxicities (62.5%). Grade 3 sensory neuropathy and fatigue occurred in 1 (6.2%) patient respectively. After neoadjuvant chemotherapy, 6 patients (37.5%) was underwent breast-conserving surgery although 2 (12.5%) cannot receive surgery because distant metastases appeared during chemotherapy. Two patients (12.5%) obtained pathological CR. At a median follow-up of 82 months (range, 6-113), 5 patients relapsed after surgery including 3 patients died. The 5-year overall survival rate was 81.2%. Conclusion: The results of this phase II study suggest that neoadjuvant weekly paclitaxel with and without trastuzumab regimen in elderly patients may achieve high clinical response rate despite the low feasibility.