[Update: adjuvant trastuzumab in HER2 positive breast cancer]

Some of the women who undergo surgery for the removal of breast cancer will need adjuvant treatment with chemotherapy, hormonal therapy, biological therapy or radiation therapy. In patients whose tumor expresses HER2, the adjuvant treatment will include Trastuzumab. In a number of prospective randomized trials performed in recent years, Trastuzumab was proven to have a significant effect in reducing by half the incidence of the recurrence of the disease and reducing the risk of death by a third. It is important to provide Trastuzumab as early as possible, together with the chemotherapy, unless treatment with doxorubicin is needed and then Trastuzumab is given later. The most significant side effect of Trastuzumab is cardiac toxicity, which is manifested in most cases by an asymptomatic decrease of the left ventricular ejection fraction in 2.3-17.3% of patients, although in most cases this has no clinical significance. Symptomatic heart failure is a rare event in Trastuzumab treated patients, occurring in 0-4% of patients and it is generally reversible with Trastuzumab discontinuation. In this review we summarize the current perspective on Trastuzumab and discuss adjuvant treatments in HER2-positive early breast cancer.