2-year follow-up of trastuzumab after adjuvant chemotherapy in HER2-positive breast cancer: a randomised controlled trial. - Smith,I.; Procter,M.; Gelber,R.D.; Guillaume,S.; Feyereislova,A.; Dowsett,M.; Goldhirsch,A.; Untch,M.; Mariani,G.; Baselga,J.; Kaufmann,M.; Cameron,D.; et al. (Lancet, 2007)