Evaluation of trastuzumab without chemotherapy as a post-operative adjuvant therapy in HER2-positive elderly breast cancer patients: randomized controlled trial [RESPECT (N-SAS BC07)]

This trial is conducted to investigate the benefit of trastuzumab monotherapy compared with a combination therapy of trastuzumab and chemotherapy in women over 70 years with human epidermal growth factor receptor type-2-positive primary breast cancer. Inclusion criteria are the following: histologically diagnosed as invasive breast cancer and received curative operation for primary breast cancer; Stage I, IIA, IIB or IIIA/M0; and baseline left ventricular ejection fraction is ≥55%. Patients are randomized to receive either trastuzumab (8 mg/kg loading dose, 6 mg/kg every 3 weeks for 1 year) plus chemotherapy selected from regimens specified on the protocol or trastuzumab monotherapy. The primary endpoint is disease-free survival. Secondary endpoints are overall survival, relapse-free survival, safety, health-related quality of life, comprehensive geriatric assessment and cost effectiveness. Patients recruitment has been commenced in October 2009. Enrollment of 300 patients is planned during the 4-year recruitment period. We hereby report the study concept.