Concomitant docetaxel plus gemcitabine versus sequential docetaxel followed by gemcitabine in anthracycline-pretreated metastatic or locally recurrent inoperable breast cancer patients: a prospective multicentre trial of the Central European Cooperative Oncology Group (CECOG)

Docetaxel (D) plus gemcitabine (G) is an active combination in anthracycline pre-treated breast cancer. Impact of sequential administration of these drugs is unclear. This trial aimed to compare concomitant DG with sequential D → G. Patients were randomised to eight cycles of gemcitabine 1,000 mg/m² on days 1 + 8 plus docetaxel 75 mg/m² on day 8, or 4 cycles of docetaxel 100 mg/m² on day 1, followed by four cycles of gemcitabine 1,250 mg/m² on days 1 + 8, in a 21-day schedule. Time to progression (TTP) was defined as primary endpoint; secondary endpoints were overall response rate (ORR), response duration (RD), overall survival (OS) and toxicity. Due to poor recruitment, the trial was terminated after 100 of a pre-planned 430 patients. Patient characteristics were well balanced. No significant difference was observed in terms of TTP, ORR, RD and OS. Grade 3/4 adverse events encompassed leucopoenia (29 vs. 68%, P < 0.001), neutropoenia (49 vs. 83%, P < 0.001) and febrile neutropoenia (4 vs. 9%, n.s.), all favouring D → G. No difference in efficacy was observed between concomitant and sequential treatment. D → G produced significantly more episodes of haematological toxicity due to the administration of docetaxel at 100 mg/m² without GCSF-support.