Trastuzumab Treatment Guidelines

Patient Selection and Treatment Regimens

• The American College of Cardiology and other guideline societies recommend that patient selection for trastuzumab treatment be based on HER2 protein overexpression or gene amplification in tumor samples, with patients defined as HER2-positive if they have an IHC score of 3+ or FISH ratio >2.0 1, 2, 3
• For early-stage HER2-positive breast cancer, recommended treatment regimens include AC (doxorubicin/cyclophosphamide) followed by T + trastuzumab ± pertuzumab, TCH (docetaxel/carboplatin/trastuzumab) ± pertuzumab, and other regimens such as AC followed by docetaxel + trastuzumab ± pertuzumab, FEC followed by docetaxel + trastuzumab + pertuzumab, and paclitaxel + trastuzumab 2

Treatment Duration and Cardiotoxicity

• The optimal duration of adjuvant trastuzumab treatment is 1 year 4
• Trastuzumab should be administered concurrently with paclitaxel as part of the AC regimen followed by paclitaxel, and the use of trastuzumab and pertuzumab with anthracyclines should be avoided due to the risk of cardiotoxicity 2