Conversion of hormone and HER-2 receptor in metachronous neck metastases from breast carcinoma.

PURPOSE: Metastases are a common event in breast cancer. The expression of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER-2) is essential for therapy and prognosis, and their conversion during disease progression potentially affects the treatment regimen. The aim was to analyze the estrogen, progesterone and HER-2 receptor expression in primary tumors and metachronous neck metastases from patients with breast cancer.

METHODS: A retrospective analysis of 27 patients with breast cancer and metachronous neck metastasis was performed. Distribution of neck metastasis to the neck levels and estrogen, progesterone and HER-2 receptor expression in primary tumor and metastasis were examined.

RESULTS: The most common localization of neck metastasis was level V. ER, PR, and HER-2 in primary tumors were positive in 48.1, 51.9, and 26.3% of patients, respectively. A loss of ER and PR in neck metastasis was observed in 22.2 and 40.7% of the patients, respectively. HER-2 change was present in 4 of 19 paired samples (21.0%).

CONCLUSIONS: The expression of ER, PR and HER-2 in neck metastases can be expected to diverge from the expression of these markers in the primary tumor. As such changes can occur during disease progression, the evaluation of biomarkers in metastatic sites should be mandatory, whenever possible, to ensure that patients are receiving the most effective treatment at all times.