O1-10-1 - Feasibility study of Dose-dense AC or EC followed by PTX for Japanese breast cancer patients

Abstract

The feasibility study of Dose-Dense chemotherapy for operable Japanese breast cancer patients(SBP 09) Dose-dense(D-D) chemotherapy for operable breast cancer revealed significant survival benefit compared to the standard chemotherapy. In western countries, it has become a standard of care. Whereas in Japan, owing to the unapproval of G-CSF primary prophylactic administration, Dose-dense chemotherapy has not been defined for a long time in spite of its efficacy. Although in recent years, the number of reports regarding D-D therapy is slightly increasing in this country, prospective feasibility study is still uncommon. To verify of the feasibility of D-D chemotherapy, we conducted a multicenter phaseII study. We enrolled patients aged under 70years, with HER2 negative and operable node-positive primary breast cancer from 10centers. The primary end point was pCR rate, and the secondary end points were safety(FN rate, completion rate),overall response rate, toxicity profile and RDI. Neoadjuvant chemotherapy with D-D AC or EC followed by PTX was administrated to eligible patients every 2weeks with Pegfilgrastim support. 50 patients were scheduled to be enrolled. 41/50 patients have been enrolled to this point. In analysis of 14/41 patients, median age was 48years(34-66), Histological subtypes were 57% Triple negative, 21% Luminal A Like, 21% LuminalB like. Clinical stageII and III were 64%, 36% respectively, and of them, StageIIIC was included at 21%. pCR rate showed 25% and, all were TN patients. Overall response rate was 100%, Grade3 or worse adverse events occurred in 33% of the patients (febrile neutropenia, pneumonia and so on). 20% of the patients were converted from q2w PTX to wPTX because of Grade3 adverse event. At the present, 80% accrual enrollment has been achieved. We plan to report the result of 50 patients full analysis.