The Great Mimicker: Metastatic Breast Carcinoma to the Head and Neck with Emphasis on Unusual Clinical and Pathologic Features

Abstract

Distant metastases are relatively common in breast cancer, but spread to the head and neck region is uncommon and can be diagnostically challenging. Pathology databases of two academic hospitals were searched for patients. The diagnoses were by morphologic comparison with the primary breast specimen (when available) or through the use of immunohistochemical stains characteristic of breast carcinoma (cytokeratin 7, mammaglobin, GCDFP15, and/or GATA3 positive-excluding new primary tumors at the respective head and neck sites). Of the 25 patients identified, only 22 (88.0 %) had a known history of breast carcinoma. Time from primary diagnosis to head and neck metastasis was highly variable, ranging from 1 to 33 years (mean = 10.9 years). The most common locations were neck lymph nodes (8 cases), orbital soft tissue (5), oral cavity (3), skull base (3), mastoid sinus (2), nasal cavity (1), palatine tonsil (1), and facial skin (1). Clinical presentations were highly variable, ranging from cranial nerve palsies without a mass lesion to oral cavity erythema and swelling to bone pain. Histologically, two cases showed mucosal (or skin)-based mass lesions with associated pagetoid spread in the adjacent epithelium, a feature normally associated with primary carcinomas. Three tumors were misdiagnosed pathologically as new head and neck primary tumors. This series demonstrates the extreme variability in clinical and pathologic features of breast cancer metastatic to the head and neck, including long time intervals to metastasis.

Keywords: Breast; Carcinoma; Head; Metastatic; Neck.

Fig. 1

a H&E section showing pagetoid infiltration of tonsillar crypt epithelium by tumor cells (arrows). b Cytokeratin 7 and c GCDFP-15 immunostains are strongly positive, showing the tumor cells infiltrating the epithelium and extending into the underlying lymphoid tissue. (a 10× magnification; b, c 20× magnification)

Fig. 2

Metastatic breast carcinoma mixed with metastatic papillary thyroid carcinoma in a neck lymph node. a Metastatic breast carcinoma cells infiltrate the stroma (asterisk) and also extend between the papillary fronds of papillary thyroid carcinoma. b A TTF-1 immunohistochemical stain highlights the tumor cells of the thyroid cancer. c An estrogen receptor immunohistochemical stain highlights the breast cancer cells (asterisk) (all figures 10× magnification)