Neo(adjuvant) trastuzumab treatment: current perspectives.

International collaboration with adjuvant trastuzumab trials showed that trastuzumab treatment improves disease-free and overall survival after or in combination with adjuvant chemotherapy. Trastuzumab treatment is already regarded as the standard therapy for HER2-positive breast cancer patients by many guidelines around the world. However, there are many uncertain issues concerning trastuzumab adjuvant treatment, for example duration of therapy, eligibility of elderly women, usability for small tumors (1 cm or less in size), and molecular marker status for individualized treatment in HER2-positive breast cancer.