Multifocal scalp hair loss.

BACKGROUND: Cutaneous metastases from internal cancer are relatively uncommon in clinical practice, but they are very important to recognize. Metastases of skin may be a herald sign in the diagnosis of internal malignancy. Scalp metastasis from breast carcinoma is reported but it is rare. We describe a 42-year-old woman who presented with three foci of alopecia on her scalp resembling alopecia areata. She was a known case of breast carcinoma 10 years prior. Radical mastectomy and total chemotherapy was done 8 years prior. An incision biopsy of an alopecic patch was done revealing metastases of breast carcinoma to the scalp. Her workup failed to find metastatic involvement of other organs. This represents a case of breast carcinoma metastatic to the scalp mimicking alopecia areata, almost 10 years after radical mastectomy, and 8 years after chemotherapy. It is important for dermatologists to be alert for atypical features of alopecia areata, such as induration, and to maintain a low threshold for biopsy in atypical cases.