A 50-year-old Caucasian woman with a history of esophageal adenocarcinoma presented with a 3-week history of right breast swelling and progressive erythema. Twenty-two months prior to presentation, she had been diagnosed with adenocarcinoma of the esophagus (T3,N1,M1a) and underwent neoadjuvant chemoradiotherapy followed by surgical resection.
On physical examination, the right breast was red, swollen (40% larger than the contralateral breast), tender to palpation, and warm to the touch (Fig. 1). No mass was palpable. On the basis of the clinical findings, inflammatory breast carcinoma was suspected. A punch biopsy revealed a poorly differentiated adenocarcinoma with extensive involvement of dermal lymphatics (Fig. 2). The clinical and histologic differential diagnosis included inflammatory breast carcinoma vs. metastatic esophageal adenocarcinoma to the skin of the breast.
To resolve this question, immunohistochemical stains for estrogen and progesterone receptors and CDX-2 (BioGenex, San Ramon, CA, USA) were performed. CDX-2 is an intestinal homeobox gene expressed in gastrointestinal epithelium and gastrointestinal tumors. The tumor nuclei were positive for CDX-2 but negative for both steroid receptors (Fig. 3), confirming the diagnosis of metastatic esophageal adenocarcinoma.