Abstract P2-16-15: 10-year outcome for women randomized in a phase III trial comparing doxorubicin and cyclophosphamide with doxorubicin and docetaxel as primary medical therapy in early breast cancer: An anglo-celtic cooperative oncology group study

Abstract

Abstract Aim: The aim of this study was to compare the long-term outcome of women with primary or locally advanced breast cancer randomised to receive either doxorubicin and cyclophosphamide (AC) or doxorubicin and docetaxel (AD) as primary chemotherapy. Patients and methods: Eligible patients with histology-proven breast cancer with primary tumours ≥ 3 cm, inflammatory or locally advanced disease, and no evidence of distant metastases, were randomised to receive a maximum of 6 cycles of either doxorubicin (60 mg/m(2)) plus cyclophosphamide (600 mg/m(2)) i/v or doxorubicin (50 mg/m(2)) plus docetaxel (75 mg/m(2)) i/v every 3 weeks, followed by surgery on completion of chemotherapy. Results: Clinical and pathologic responses have previously been reported 1. Time to relapse, site of relapse, and all-cause mortality were recorded. This updated analysis compares long-term disease-free (DFS) and overall survival (OS) using stratified log rank methods. A total of 363 patients were randomised to AC (n = 181) or AD (n = 182). At a median follow-up of 119 months, there is no significant difference between the two groups for DFS (P = 0.274) and OS (P = 0.327). The 10-year DFS for AC is 54% (95% CI 47-62%) and for AD 60% (95% CI 52-67). The 10-year OS is 49% (95% CI 42-57%) for AC and 51% (95% CI 43-58%) for AD. Metastatic breast cancer accounted for 89% of deaths in those treated with AC and 86% in those treated with AD. Estrogen receptor (ER) and nodal status were independent prognostic factors for DFS and OS (p<0.0005), but not the chemotherapy regimen (p=0.282 for DFS, p=0.426 for OS). Conclusions: This was one of the first studies to evaluate taxanes versus anthracyclines in the neoadjuvant setting. Our mature data do not support an added clinical benefit for the simultaneous administration of AD compared to AC. This supports current practice with respect to sequential treatment with taxanes followed by anthracyclines leading to an increase in pathological complete response rate and better survival outcomes. 1. Evans TR, Yellowlees A, Foster E et al. Phase III randomized trial of doxorubicin and docetaxel versus doxorubicin and cyclophosphamide as primary medical therapy in women with breast cancer: an Anglo-Celtic cooperative Oncology group study. J Clin Oncol 2005, 23: 2988–2995. Citation Format: Chara Stavraka, T. R. Jeffry Evans, Joanna Dunlop, Helena Earl, David A. Cameron, Robert E Coleman, Timothy Perren, Robert CF Leonard, Janine L Mansi. 10-year outcome for women randomized in a phase III trial comparing doxorubicin and cyclophosphamide with doxorubicin and docetaxel as primary medical therapy in early breast cancer: An anglo-celtic cooperative oncology group study [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P2-16-15.