A 42- year-old female with recent diagnosis of stage III malignant melanoma in her leg presents for evaluation of a palpable right breast lump.

On mammography, in the patient’s area of concern in the right 8:00 position, a well-circumscribed, round mass is seen measuring 5 mm. Just adjacent to this is an additional 10 mm round, well-circumscribed mass. On physical examination, there is a palpable superficial mobile lump in the right 8:00 area of concern.  Ultrasound demonstrates a cyst measuring 4 mm, corresponding to the area of concern at 8:00. At the 8:30 position, there is a heterogeneous round mass noted measuring 12 x 9 x 6 mm.

Needle core biopsy under ultrasound guidance was performed of the largest mass at 8:30, with pathology revealing metastatic malignant melanoma.

Metastases to the breast are rare, with melanoma and lymphoma being the two most commonly seen. Metastasis to the breast usually presents as an asymptomatic lesion in the upper outer quadrant of the breast. Clinically they are seen as well circumscribed lesions. Malignant melanoma accounts for only 1.3-6.6% of all malignant mammary tumors and are often seen in younger patients due to the larger amount of vascularity in the breasts.  The average age of patients ranges from 38-40 years.

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Image IQ: 42-year-old Woman with Recent Stage III Malignant Melanoma Diagnosis