Metastatic breast disease from cutaneous malignant melanoma

Malignant melanoma is one of the most rapidly increasing cancer in the world. Breast metastases from melanoma are uncommon but could reflect a widespread disease.

We report a case of malignant widespread melanoma presenting with bilateral breast nodules in a 39 year-old pre-menopausal Caucasian woman with an history of cutaneous melanoma of the trunk. Breast clinical examination revealed the presence of a hard and mobile lump located on the left breast. Ultrasound detected two bilateral nodules corresponding to oval opacities with well-defined edges and without calcifications or architectural distortion on mammography. Fine needle aspiration cytology performed on both breast nodules confirmed that the breast lesions were metastases from primary cutaneous malignant melanoma. A total-body CT examination detected brain, lung and abdominal lymph nodes metastases.

The breast represents an uncommon site of metastatic disease from extra-mammary tumors. Imaging features of breast metastases from melanoma usually do not allow a differential diagnosis with breast primary tumors. Breast metastases may be asymptomatic or palpable as dense and well-circumscribed nodules. Breast metastases indicate a widespread disease and should lead to avoid aggressive surgical procedures because of the poor prognosis of patients affected by metastatic melanoma.

The detection of bilateral breast metastases from melanoma is highly suggestive of metastatic multi-organ disease and could be useful to address the therapeutic approach.