Cutaneous metastases in patients with metastatic carcinoma: A retrospective study of 4020 patients

Background: Most previous studies have found that cutaneous metastases occur infrequently and are rarely present at the time the cancer is initially diagnosed. Objective: We studied patients with metastatic cancer to determine the overall frequency of skin metastases, the frequency that these were the first sign of extranodal disease, and the clinical and histologic features of the cutaneous lesions. Methods: A 10-year period of tumor registry files was searched for patients with metastatic carcinoma and melanoma. For patients with skin metastases, medical records and pathology reports were also examined. Results: Of 4020 patients with metastatic disease, 420 (10%) had cutaneous metastases; in 306 of them the skin metastases were the first sign of extranodal metastatic disease. Breast cancer and melanoma were the most common. Nodules were the most frequent clinical presentation, although inflammatory, cicatricial, and bullous lesions were also noted. Incisional metastases were common. Histologic findings most frequently revealed adenocarcinoma that was sometimes suggestive of the site of origin. After recognition of skin metastases, mean patient survival ranged from 1 to 34 months depending on tumor type. Conclusion: Cutaneous metastases are not uncommon and frequently are the first sign of extranodal metastatic disease, particularly in patients with melanoma, breast cancer, or mucosal cancers of the head and neck.