Incidence of chemotherapy-induced nausea and vomiting associated with docetaxel and cyclophosphamide in early breast cancer patients and aprepitant efficacy as salvage therapy. Results from the Spanish Breast Cancer Group/2009-02 study.

BACKGROUND: Docetaxel-cyclophosphamide (TC) has become a common regimen in moderate-high-risk early breast cancer (EBC), but the incidence of chemotherapy-induced nausea and vomiting (CINV) with this regimen is not well established. This trial investigates the effect of guideline-consistent prophylaxis on CINV related to TC regimen and explores the efficacy of aprepitant among resistant patients.

PATIENTS AND METHODS: This prospective multicentre study enrolled 212 chemotherapy-naïve EBC patients receiving T-75 mg/m(2) and C-600 mg/m(2). Antiemetic therapy on the first cycle consisted of dexamethasone for 3 d plus 5-hydroxytryptamine (5-HT3) antagonists on day 1, according to Multinational Association of Supportive Care in Cancer guidelines. The primary end-point was complete response (CR) (no emesis and no need of rescue treatment within the initial 120 h). Patients failing CR on cycle 1 entered in a single-arm study exploring the efficacy of aprepitant on the second cycle. Patients' diaries and Functional Living Index-Emesis (FLIE) questionnaires were collected in cycles 1 and 2.

RESULTS: Among the 185 evaluable patients on cycle 1, 161 (87%, 95% confidence interval [CI]: 82.2-91.8) achieved a CR. Twenty-three patients received aprepitant on cycle 2, and 12 reached a CR (52.2%, 95% CI: 31.8-72.6). The absence of CR had a very substantial impact on quality of life on cycles 1 (FLIE before and after: 23.8-38.1, p = 0.0124) and 2 (18.3-42.9, p = 0.0059).

CONCLUSIONS: Guideline-consistent antiemetic prophylaxis for the TC regimen is associated with a low incidence of CINV. Aprepitant is effective as secondary prevention of CINV and should be considered as rescue therapy in patients treated with moderate emetogenic chemotherapy.