- Lapatinib (GW572016, Tykerb, 750-1500 mg/d orally daily until the day of the definitive surgery) Treatment is planned for 6 cycles unless there is evidence of unacceptable toxicity, disease progression or inadequate efficacy (defined as a decrease in tumor size <25% after 4 courses measured by ultrasound or MR-mammography), or if the patient requested to be released.