Quality of life during and after adjuvant anthracycline-taxane-based chemotherapy with or without Gemcitabine in high-risk early breast cancer: results of the SUCCESS A trial.

PURPOSE: In high-risk early breast cancer, adjuvant taxane-Gemcitabine combinations result in a recurrence-free survival similar to single-agent taxanes. However, haematologic toxicities and need for dose reductions are more frequent in combinations. Which option ultimately provides a better quality of life (QoL) is unknown. We compared the QoL curves before, during, and up to one year after three cycles of Fluorouracil-epirubicin-cyclophosphamide followed by three cycles of Docetaxel-Gemcitabine or Docetaxel.

METHODS: Overall, 3691 women with recent R0-resection of a primary epithelial breast cancer participated in the nationwide SUCCESS A clinical trial. The centres sent QoL questionnaires of the European Organisation for Research and Treatment of Cancer before and up to 15 months after randomisation to Docetaxel-Gemcitabine versus Docetaxel. Multilevel analysis by chemotherapy arm estimated the QoL time curves, questionnaire return, and dropout.

RESULTS: The combination caused one-point higher global QoL (95% confidence ±1; p = 0.05) and 1.1 lower odds of adherence to the outcome (95% confidence 1.0-1.1; p = 0.23) than the monotherapy. In both groups, a 10-point decrease during therapy preceded a 16-point increase after chemotherapy (p < 0.001). The secondary QoL outcomes showed transient superiority of the combination at the end of chemotherapy. Discontinuation from chemotherapy and its reasons were equal in both groups.

CONCLUSIONS: While patients perceive a one-point QoL difference as meaningless, a six-point increase is clinically relevant for them. That is, both regimens cause the same relevant long-term QoL improvement. With the similar recurrence-free survival, the lower toxicity, and the shorter chemotherapy duration in mind, taxanes without Gemcitabine are the preference. This challenges previous recommendations supporting combinations.