Trastuzumab is a monoclonal antibody that binds to the HER2 tyrosine kinase. When given with chemotherapy, trastuzumab extends survival of breast cancer patients with HER2-positive cancer compared with chemotherapy alone. but little evidence exists to support this time period. 12 months of treatment became the accepted standard because it was the only duration assessed in the large trials that established safety and efficacy of trastuzumab as an adjuvant treatment for HER2-positive breast cancer. (Source: LANCET)MedWorm Sponsor Message: Have a look at The Breast Cancer Daily, the new breast cancer portal with all the latest breast cancer news and research powered by MedWorm, updated daily.