Omission of Radiation in Patients With Her-2 Positive Breast Cancer

Participants, ages 40 and older diagnosed with stage I or stage II her-2 positive, node negative breast cancer patients will be recommended to continue trastuzumab +/- pertuzumab therapy after surgery to complete a full year of therapy as standard of care under the clinical management of the patient's medical oncologist.

Once neoadjuvant chemotherapy has been completed, the patient will be separated in to one of three arms based on a set of criteria for each. If the patient wishes to take part in the study, but does not have a lumpectomy with sentinel lymph node biopsy showing pCR, the patient will be placed in to Arm C and will proceed with radiation as standard of care. If the patient wishes to take part in the study, and has a lumpectomy with sentinel lymph node biopsy showing pCR, but does not agree to omission of radiation, the patient will be placed in to Arm B and will proceed with radiation as standard of care. If the patient wishes to take part in the study, and has a lumpectomy with sentinel lymph node biopsy showing pCR and agrees to omission of radiation, the patient will be placed in to Arm A with follow up assessments occuring at 1 month post-op, and every 3 months up to 5 years post-op.

Data will be collected on local, regional and distant recurrence at each follow-up.The self-administered FACT-B+4 quality of life questionnaire will be given to patients at baseline, at first postoperative visit, and at the one year post-operative visit.

Patients enrolling prior to chemotherapy will be asked to fill out the Breast-Qâ„¢ at the time of their first surgical consultation. Patients enrolled post-surgery will be asked to fill out the Breast-Qâ„¢ at their first post-operative visit. All patients will be asked to fill out the Breast-Qâ„¢ at their yearly postoperative visits. The Breast-Qâ„¢ is a validated patient assessment of breast cosmesis. This tool has both pre operative and post-operative components. Pre-operative Breast-Qâ„¢ questionnaire data is not required of participants in this study who enroll postoperatively.