Invasive Paget Disease of the Nipple of Luminal-B Subtype With Axillary Lymph Node Metastasis in a 60-Year-Old White Woman.

Herein, we report a rare case of invasive Paget disease of the nipple with axillary-lymph-node metastasis in a 60-year-old white woman. The patient had intermittent, bloody nipple discharge without skin changes of the nipple-areolar region. We considered the clinical diagnosis of intraductal papilloma. A subareolar core biopsy revealed invasive ductal carcinoma in deep dermal tissue without the overlying epidermis biopsied. The patient underwent total mastectomy and axillary sentinel lymph-node biopsy that demonstrated invasive Paget disease of the nipple with 3.5-mm depth of invasion, ductal carcinoma in-situ in the underlying breast parenchyma, and macrometastasis (5.0 mm) in the sentinel lymph node. Prognostic marker studies of the metastatic site revealed a profile similar to that in the invasive mammary Paget disease (estrogen receptor [ER]+/progesterone receptor [PR]+/human epidermal growth factor receptor 2 [HER2]-/proliferation index [Ki-67] of 30%). The patient received adjuvant chemotherapy and experienced no disease recurrence at 20-months of follow-up. This case of luminal-B subtype invasive Paget disease as the source of regional metastasis is unique in the literature, to our knowledge. Copyright© by the American Society for Clinical Pathology (ASCP).