When you join this study, your doctor will first review your health information to ensure your safety. Throughout the study, you will have regular exams and tests to monitor your health. While most of these are standard care, some are for research purposes only, such as completing two forms. If you speak English or Spanish, you will fill out a form called PROCTCAE about side effects you experience, which helps researchers understand how cancer and its treatment affect people. You will also complete a form about any extra costs you incur during treatment. Since these forms are for research, your answers will not be shared with your study doctor; you should speak directly with your doctor or nurse about any serious health concerns. Your responsibilities as a participant include: keeping all study appointments; reporting all medications, supplements, and any side effects; and informing your doctor of any outside medical visits, hospital stays, or participation in other studies. Finally, you must not become pregnant, breastfeed, or father a child while in the study. You must also inform your study doctor immediately if you or your partner become pregnant during the study or within seven months after your last dose of trastuzumab or pertuzumab.