Unusual cutaneous metastatic carcinoma.

Most of metastatic tumors to the skin are from primary tumors of the breast, lung, or from melanoma; metastases to the skin from primary carcinomas at other sites are rare. Cutaneous metastases of visceral carcinomas most often occur in patients with advanced disease, and are associated with a poor prognosis. We report 6 cases of nonmammary, nonpulmonary carcinoma metastatic to the skin. Most patients were elderly with advanced disease at the time of diagnosis of skin metastasis. The primary tumor sites included the thyroid, esophagus, biliary tract, ovary, and prostate. Awareness of these rare cases of metastasis to the skin will help pathologists and clinicians make the correct diagnosis.