Cutaneous zosteriform squamous cell carcinoma metastasis arising in an immunocompetent patient.

Cutaneous metastases from internal malignancies or primary skin cancers are uncommon, and a zosteriform pattern is very rare. Histologically, these cutaneous metastases usually appear as malignant epithelial cells located throughout the dermis or subcutaneous fat and without connection to the overlying epidermis. The presence of melanocytes in such lesions is atypical. Moreover, although zosteriform cutaneous metastases of cutaneous squamous cell carcinoma have previously been described in immunosuppressed patients, they have not been reported in immunocompetent patients. We report an unusual case of a woman with cutaneous hyperchromic zosteriform metastases, clinically mimicking a metastatic melanoma but appearing histologically as epidermotropic and pigmented metastases of a cutaneous squamous cell carcinoma.