Purpuric plaque on the neck of a patient with breast carcinoma.

Sir,

A 78-year-old woman presented with a purpuric plaque over the left lateral aspect of her neck upon admission for urosepsis due to Klebsiella. The patient was nonverbal and the only caretaker to offer her history was unable to provide any relevant information on the lesion. Her medical history was notable for lobular carcinoma of the breast with multiple osseous metastases postlumpectomy, chemotherapy, and multiple radiation therapy. She was afebrile, normotensive, and had a normal pulse on initial examination. Physical examination was notable for a 10 cm purpuric minimally indurated plaque over the left lateral aspect of her neck and jawline [Figure 1].

Figure 1

A 10 cm purpuric minimally indurated plaque over the left lateral neck and jawline

Histopathologic examination demonstrated a poorly differentiated infiltrating adenocarcinoma, with extensive lymphatic and vascular invasion [Figures 2 and 3]. Immunohistochemistry showed strong positive staining of tumor nuclei with antibodies to estrogen receptor protein, progesterone receptor protein, cytokeratin 7, and mammaglobin, with negative staining of tumor cells with antibodies to Her2/neu protein. Given the histopathology and the clinical presentation of the lesion, a diagnosis of telangiectatic metastatic breast carcinoma (TMBC) was made.

Figure 2

H and E, ×40 reveals poorly differentiated adenocarcinoma, with extensive lymphatic and vascular invasion

Figure 3

H and E, ×4 reveals poorly differentiated adenocarcinoma, with extensive lymphatic and vascular invasion

Breast carcinoma, the second most common cancer among women after nonmelanoma skin cancer, has an incidence of skin metastases of 23.9%.[1] In a retrospective review by Mordenti et al., cases of skin metastases specifically from breast carcinoma were examined to determine the most common clinical and histopathologic presentations. Skin papules and/or nodules were found in 80% of patients, TMBC in 11%, erysipeloid carcinomas in 3%, “en cuirasse” carcinomas in 3%, alopecia neoplastica in 2%, and a zosteriform type in 0.8%.[2345678] TMBC clinically can present as a patch of telangiectasias, a purpuric plaque, or as lymphangioma circumscriptum–like pseudovesicles.[9]

Differentiating TMBC from other cutaneous lesions can be challenging based on clinical features alone, due to the ability of the tumor to mimic arteriovenous malformation, angiotropic lymphoma, hemangioma, Kaposi's sarcoma, angiosarcoma, and benign atypical vascular proliferations.[10] Histopathology of TMBC shows aggregates of atypical lobular cells and erythrocytes with dilated lymphatic channels in the papillary dermis; sometimes intravascular calcifications can be seen. A study analyzing the pathology of various cutaneous metastatic breast carcinomas showed that intralymphatic tumor-cell emboli were common in those with TMBC.[11]