Addition of capecitabine to a standard chemotherapy regimen for breast cancer improves recurrence-free survival. However, increased adverse events mean treatment with capecitabine is frequently discontinued. These are the findings of an published in the December edition of The Lancet Oncology, written by Professor Heikki Joensuu, Helsinki University Central Hospital, Finland, and colleagues.

In this randomised controlled trial, 1500 women with moderate-to-high risk early breast cancer were assigned to either three cycles of capecitabine and docetaxel followed by three cycles of cyclophosphamide, epirubicin, and capecitabine (capecitabine group, n=753), or to three cycles of docetaxel followed by three cycles of cyclophosphamide, epirubicin, and fluorouracil (control group, n=747). The control combination was representative of a regimen frequently used in Finland and Sweden, and similar to the regimen administered in many other countries. The primary endpoint was recurrence-free survival. In this study, the authors carried out a planned interim analysis after 3 years’ median follow-up.

The team found that recurrence-free survival at 3 years was better with the capecitabine regimen than with control (93% vs 89%). The capecitabine regimen was associated with more cases of grade 3 or 4 diarrhoea (6% vs 3%) and hand-foot syndrome* (11% vs <1%) and the control regimen with more occurrences of grade 3 or 4 neutropenia** (98% vs 86%) and febrile neutropenia (9% vs 4%). More patients discontinued planned treatment in the capecitabine group (24% vs 3% in the control arm).

The authors say: “The capecitabine-containing chemotherapy regimen reduced breast cancer recurrence compared with a control schedule of standard agents. Capecitabine administration was frequently discontinued because of adverse effects... Our results suggest that integration of capecitabine upfront with potentially synergistic chemotherapeutic agents and into several cycles might be an effective treatment strategy.”
They add: “Integration of capecitabine was associated with frequent discontinuation of planned chemotherapy, but most patients could tolerate all six scheduled cycles. Studies that focus on further refinement of the current chemotherapy regimen are warranted.”

In an accompanying comment, Dr Ruth M. O’Regan. Emory Winship Cancer Institute, Atlanta, GA, USA, says: “Although the findings of this trial are not practice-changing, they are intriguing and could merit further assessment in a larger trial. However, the significant toxicity noted with the addition of capecitabine to the taxane–anthracycline backbone dampens enthusiasm for further studies of this approach. More importantly, it is imperative that we take a more rational approach to the treatment of early-stage breast cancer by tailoring our treatment approaches to molecular phenotypes.”

Source: The Lancet Oncology