ABCSG-24 Finds Neoadjuvant Capecitabine Improves Complete Response in Early Stage Breast Cancer

The Austrian Breast and Colorectal Cancer Study Group (ABCSG) presented new data from the ABCSG-24 trial, which has been investigating adjuvant treatment with capecitabine (Xeloda) plus a standard chemotherapy regimen of epirubicin and docetaxel (Taxotere) in women with early stage breast cancer. An impressive 24% of women who underwent treatment with capecitabine and cytotoxic agents had complete response compared to a rate ranging from 6% to 18% for standard chemotherapy.

The randomized phase III study recruited 536 women with HER2-positive or HER2-negative early stage breast cancer (without distant metastases) between 2004 and 2008. Based on risk factors, patients were randomized 1:1 to receive standard chemotherapy with or without capecitabine for six 21-day cycles. Patients in the capecitabine arm took 1000 mg/m² per day for 14 days.

At the time of surgery, 24% of the patients in the capecitabine arm had pathologic complete response compared with 16% in the chemotherapy-alone group (P = .02). Complete pathologic response was defined as “complete disappearance of tumor cells in the breast and in the lymph nodes,” which is associated with a much better prognosis for long-term survival. The capecitabine-based regimen did result in increased toxicity, but adverse effects were described as manageable. The number of patients who completed all 6 treatment cycles was similar in each group: 94% in the capecitabine group and 96% in the chemotherapy-only group.

In a press release, Professor Günther Steger, Division of Oncology, Department of Internal Medicine I, Medical University of Vienna, General Hospital Vienna, Austria, said, “These new data show that adding capecitabine to epirubicin and docetaxel neoadjuvant regimens when treating women with early breast cancer results in increased efficacy compared to epirubicin and docetaxel alone.” He suggested that the results from this study might lead to improved treatment for women with early stage breast cancer, possibly prolonging overall survival.

Nearly 30% to 50% of patients who receive a diagnosis of early stage breast cancer will relapse, even after chemotherapy, according to the study’s presenters. They note that their study adds to a growing body of evidence that suggests a neoadjuvant regimen containing capecitabine has enhanced efficacy compared with standard chemotherapy alone.

ECCO/ESMO Abstract 4BA