Skin clues to primary and metastatic malignancy.

A new or unusual skin lesion may be the first sign of an internal malignancy, a primary skin cancer or a cutaneous metastasis of carcinoma in another site. Patients with carcinoma that has metastasized to the skin commonly present with lesions in the area overlying the neoplasm, but the morphology, pattern and distribution of cutaneous metastases may vary. Patients with sarcoma, leukemia or lymphoma may also initially present with cutaneous lesions, or lesions may develop later in the course of the disease. Biopsies of suspicious lesions should always be performed.