Parotid gland metastasis of a breast cancer.

Parotid gland metastases from malignant tumors are extremely rare. A 61-year-old woman was diagnosed with an early breast cancer with no expression of oestrogen and progesterone receptors. Five years later the patient presented a tumour in parotid gland. After total parotidectomy, microscopic analysis of the gland demonstrated an invasive duct carcinoma (IDC) with positive expression of oestrogen receptor. The patient was treated with chemotherapy followed by complementary local radiotherapy. Diagnosis of a metastasic tumour in parotid gland poses a challenge. In our case an immunohistochemical study of oestrogen receptor was fundamental to establish a diagnosis.