Evaluate The Accuracy Of Breast MRI Biopsy In Diagnosing A Complete Tumor Response For Some Women Following Neoadjuvant Chemotherapy For Breast Cancer

Inclusion Criteria

• •Women age 18 years or older
• •Confirmed histologic diagnosis of operable HER2 overexpressing (ER\<10%, PR\<10%, and HER2 2+ or FISH amplified) OR triple negative (ER\<10%, PR\<10%, and HER2 0/1+ or 2+/FISH not amplified) OR ER positive invasive ductal or invasive lobular breast cancer including MSKCC pathology confirmation
• •Operable breast cancer treated with NAC undergoing either breast conservation or total Mastectomy who have had a post-NAC clinical bilateral breast MRI demonstrating a complete imaging response, which is defined as no residual tumor enhancement.
• •No indication of distant metastases (M0)
• •Tumor site amenable to MRI guided biopsy as determined by the radiologist
• •Definitive surgery being performed at MSKCC within within 0-60 days of completing NAC
• •ECOG performance status score of 0 to ≤ 2 and or KPS performance status score of 80% to 100%
• •Women of childbearing potential (WOCBP) must not be pregnant.
• •Women must not be breastfeeding
• •Willing and able to provide informed consent and adhere to the study visit schedule and plan as specified in this protocol