Comparing 6 Months Versus 12 Months of HER2-Targeted Therapy After Chemotherapy for Early-Stage HER2-Positive Breast Cancer with Complete Response

What this Trial Is About

This trial evaluates whether a shorter duration of HER2-targeted therapy is as effective as the standard length for treating early-stage HER2-positive breast cancer in patients who had a complete response after preoperative chemotherapy with trastuzumab. The study focuses on comparing 6 months versus 12 months of combined neoadjuvant and adjuvant HER2 blockade and also assesses quality of life and safety outcomes. The trial aims to determine if shorter treatment can maintain similar recurrence-free survival and reduce side effects. Participants are randomly assigned to receive trastuzumab and possibly pertuzumab either intravenously or subcutaneously every 21 days. One group receives treatment for up to 17 cycles about 12 months, while the other group receives treatment for up to 9 cycles about 6 months, as long as no disease progression or unacceptable toxicity occurs. Throughout the trial, patients undergo heart function tests echocardiography or MUGA and breast imaging mammography, ultrasound, or MRI. Optional blood and tissue samples may be collected for additional studies. Participants are followed for recurrence and survival for up to 10 years after treatment begins, with check-ins every 6 months for the first 5 years and then yearly afterward. The study measures recurrence-free survival, overall survival, local and distant cancer recurrence, and patient-reported quality of life using specific questionnaires. It also monitors serious side effects and symptoms like diarrhea, fatigue, and rash. This comprehensive follow-up helps evaluate long-term outcomes and treatment impact.

ShortStop-HER2: 12 Months vs. 6 Months of HER2-targeted Medications for People With HER2+ Breast Cancer Who Had a Pathologic Complete Response After Chemotherapy Plus Trastuzumab