Abstract

Cutaneous metastases as a primary presentation of occult breast carcinoma (OBC) is a rare sign of this type of malignant disease. Cutaneous metastases (CM) are neoplastic infiltrations of the skin that originate from distant malignant tumors. We described the diagnosis and treatment of a woman in her mid-50s who presented with extensive papulonodular pruritic skin lesions that started a year ago mostly in the right breast chest wall, right axillary region, and right arm. The patient denied a history of breast lumps. Skin biopsy revealed cutaneous metastases of a high-grade invasive ductal carcinoma of the breast with extensive dermal lymphatic invasion. Further investigation indicated that the cells were positive for cytokeratin 7 and GATA3 and negative for p63 confirming their breast origin. Immunohistochemistry analysis revealed that the tumor was estrogen-receptor negative, progesterone-receptor negative, and human epidermal growth factor receptor 2 positive. The patient was treated with carboplatin, docetaxel and trastuzumab. Evaluation after 6 cycles of chemotherapy showed stable disease.