Paclitaxel and trastuzumab are drugs used in the standard treatment of early-stage breast cancers that overproduce a protein called HER2 (the target of trastuzumab). Despite this treatment, however, some women experience a recurrence of their cancer. Lapatinib is a newer drug that targets HER2 in a way different than trastuzumab; it is approved for the treatment of advanced breast cancer when given in combination with certain other drugs.
The purpose of this study is to see if it is feasible to give paclitaxel, trastuzumab, and lapatinib together in women with early-stage HER2-positive breast cancer. Researchers are conducting this study to observe the side effects of this drug combination in these patients.