Sometimes moles are not cancerous, but they donÕt look normal on clinical exam. TheyÕre not completely benign, but theyÕre not cancer. TheyÕre in a stage somewhere in between. That in between stage is called the atypical nevus. An atypical nevus can be asymptomatic, but in clinical exam, you see five specific patterns that are important to discuss. We call them the A, B, C, D, and E clinical exam findings. A is for asymmetry. The mole isnÕt perfectly round. You canÕt draw a line in between it and reflect on itself. B, border. The border is irregular. ItÕs not a smooth curve, but more like a jigsaw puzzle. C for color. Instead of it being one simple color, it can be one, two, three, or four shades of brown or black. D diameter. Generally, an atypical nevus will be bigger than six millimeters, or the size of a pencil eraser. And lastly, E is evolution. Any mole that quickly changes, grows, itches, or bleeds. Atypical nevi are treated in many ways. Sometimes we simply watch them clinically, and when weÕre worried, we remove them with surgery. In general, any patient who has a strong family history of melanoma and has a quickly changing mole, or a new mole that they have not seen before, are reasons for us to examine in clinic. However, in general, an atypical nevus or melanoma can happen in anyone without a family history of melanoma. So if the patient is concerned, we want to see the patient.