Benign Cutaneous Tumors

Tumors of the cutaneous surface may arise from the epidermis, dermis, or subcutaneous tissue or from any of the specialized cell types in the skin or its appendages. Broad categories include tumors derived from epithelial, melanocytic, or connective tissue structures. Within each location or cell type, lesions are classified as benign, malignant, or, in certain cases, premalignant. Benign epithelial tumors include tumors of the surface epidermis that form keratin, tumors of the epidermal appendages, and cysts of the skin. Melanocytic (pigment-forming) lesions are very common. One of the most frequently encountered forms is the nevus cell nevus. Tumors that are derived from connective tissue include fibromas, histiocytomas, lipomas, leiomyomas, and hemangiomas. This chapter provides an overview of each type of tumor, including sections on epithelial tumors, tumors of the epidermal appendages, familial tumor syndromes, melanocytic tumors, neural tumors, connective tissue tumors, vascular birthmarks, acquired vascular disorders, Kimura disease, lipoma, leiomyoma, and lymphangioma circumscriptum. The sections discuss various forms and their diagnosis, differential diagnosis, and treatment. Figures accompany the descriptions. This chapter contains 83 references, 26 highly rendered figures, and 5 MCQs.