Cutaneous metastases: A great imitator

Neoplastic cells originating from a primary cancer can uncommonly spread to the skin, where they suggest a poor prognosis for the patient. In women, melanoma, breast, ovarian, oral cavity, and lung are the most common primary sources; in men, melanoma, lung, colon, and squamous cell carcinoma of the head and neck predominate. The classic presentation of cutaneous metastases is a firm, painless, flesh-colored to an erythematous dermal nodule (or nodules); however, several other presentations, including inflammatory, cicatricial, and bullous lesions, have been reported. Cutaneous metastases may also mimic benign conditions such as lipomas, hemangiomas, or cellulitis. A high degree of clinical suspicion is necessary, and the diagnosis is confirmed by biopsy, which may also be used to establish the primary malignancy if unknown, as the histopathologic appearance of the metastatic tissue may mimic the primary tumor. Treatments include excision of the metastases, chemotherapy, immunotherapy, radiation, and/or palliative care.