Dose-dense chemotherapy for primary breast cancer

Dose density is a relative term referring to the administration frequency of chemotherapy drugs and regimens compared with standard regimens. The concept of dose-dense chemotherapy is based on the hypothesis that maximal chemotherapy effectiveness can be achieved by scheduling the interval of chemotherapy to correspond to the period of most rapid tumor growth. The present paper aims to outline the theoretical framework for dose-dense chemotherapy and to review recent clinical trials addressing this concept within adjuvant breast cancer treatment.

Several randomized trials have been conducted to test the feasibility and effectiveness of anthracycline and/or taxanes-based dose-dense strategies. They demonstrate that using hematopoietic growth factor support has made dose-dense therapy safe and feasible. Dose-dense strategies have been associated with a modest impact on disease recurrence and overall survival of patients with early-stage breast cancer. Subset analyses suggest increased benefits for specific tumor subtypes such as hormone receptor-negative, highly proliferative or HER2 overexpressing tumors.

Trials in unselected patients with early-stage breast cancer have demonstrated promising results for dose-dense chemotherapy. Further studies are needed to define the optimal regimen and the patient population that will receive the greatest benefit from this therapy.