Abstract
Basal cell carcinoma (BCC) is the most common type of skin cancer. The superficial subtype of BCC may present as a scaly erythematous plaque. This case report discusses a large BCC on the left scalp of an elderly patient who was treated for many years as plaque psoriasis. This report also discusses scouting biopsies as a valuable tool for the dermatologic surgeon to aid in cancer mapping. Finally, we describe the use of serial excisions using Mohs micrographic surgery on the advancing edge as a therapeutic option for large BCCs in high-tension areas.