Breast Cancer Tumoral Heterogeneity: A Case Report of the Discovery of Multiple Heterogeneous Foci of Invasive Carcinoma Arising Within the Right Breast

<p><strong><span>Abstract</span></strong></p> <p><span>We report the case of a 50-year-old female with bilateral breast implants who presented with indeterminate, pleomorphic, linear, branching ductal calcifications in the right breast. Following unsuccessful stereotactic biopsy, the patient underwent a right breast excisional biopsy with wireless localization. The biopsy identified ER positive, PR positive, invasive ductal carcinoma (IDC) with mucinous features and ductal carcinoma in situ (DCIS). In order to obtain adequate margins, the decision was made to proceed with bilateral mastectomy with reconstruction and right sentinel lymph node biopsy. Final pathology revealed multiple, heterogeneous foci of invasive carcinoma arising within the right breast including invasive tubular carcinoma (ER and PR positive, HER2 negative), high-grade DCIS and moderately differentiated invasive ductal carcinoma (ER and PR negative, HER2 positive). Ultimately, adjuvant hormonal therapy, HER2 targeted therapy and chemoradiotherapy were recommended.</span></p>