Mimickers of Carcinoma

Each year in the United States approximately 1,000,000 cases of non-melanoma skin cancer are diagnosed. Of these cases roughly 80% are basal cell carcinomas and 20% are squamous cell carcinomas. 1 A small percentage of these carcinomas are rare malignancies of adnexal origin and cutaneous metastases. In the typical practice of dermatopathology carcinomas are commonly seen and expected. However, there are also numerous benign conditions of the skin that can mimic cutaneous carcinomas and lead to an erroneous diagnosis of malignancy. In this presentation we will review some of the benign mimics of cutaneous carcinomas. These mimics may take the form of reactive, primary inflammatory, infectious, and benign neoplastic processes. The clinical presentation and histopathology of these mimics will be examined and ancillary studies that aid in confirming the correct (benign) diagnosis will be presented.