Cutaneous melanocytic nevi
- Common nevi
- Small (lesions are usually less than 6 mm), flat, and round
- Border is regular, smooth, and well-defined
- Color is homogeneous (usually no more than 2 shades of brown)
- Any site is affected
- Some people have only 1 to 5 moles; others have more than 100
- Dysplastic nevi
- Large (usually more than 5 mm) with a flat component
- Can be round, oval, or other shape
- Border is characteristically fuzzy and ill-defined
- Color is usually brown
- Can be mottled with dark brown, tan, or pink
- Occur most commonly on trunk
- Blue nevi
- Well-circumscribed, slightly raised or dome-shaped papules, often described as slate-blue in color
- Usually less than 5 mm in diameter
- Occur primarily on face, scalp, and dorsal surfaces of hands and feet
- Usually acquired in childhood and adolescence
- Do not demonstrate atypical features
- Compared visually with common, dysplastic, and blue nevi, melanoma lesions tend to be:
- Larger (often more than 6 mm)
- More irregular in border
- More heterogeneous in color (wider variation, more shades)
- Colors range widely and include tan-brown, dark brown, black, pink, red, gray, blue, and white
- Biopsy is needed to differentiate if lesion is not clearly benign
