Malignant melanoma and carcinoma of the breast.

Five patients with breast cancer and malignant melanoma are reported. Two patients had a third primary malignancy. In 4 out of 5 patients the breast tumor was the initial tumor discovered, and in 4 out of 5 the second tumor evolved metachronously. No specific carcinogenic factor could be established. The low malignancy potential of the melanoma by pathologic criteria may explain the lack of previous reports of this association.