Module 3 - Skin & Soft Tissue Lesions
Benign Skin Lesions
1.) Nevi
Junctional nevus
Junctional nevus cells
- Small (<6 mm), well-circumscribed, light brown or black macules
- Located in epidermis at dermal-epidermal junction
- Found anywhere on the body
- Rarely develop in people >40 yrs old; if noted, should be considered possible early melanoma
Dermal Nevus
- Small, brown or black, slightly elevated lesions
- Dermally located
- May have excess of hair
Compound Nevus
- Small, well circumscribed, uniformly pigmented, raised lesions
- Both junctional and intradermal elements
- May have excess of hair
2.) Keratoses
Seborrheic keratoses
Seborrheic keratoses
- Multiple raised, irregularly rounded, benign skin lesions (stuck-on appearance)
- Verrucous (wart-like), friable, waxy surface
- Variable pigmentation (yellowish to brownish black)
- Originate from epidermal cells
- Found on face, neck and trunk
- Most often seen in elderly population
- Surgical excision for small, isolated lesions; sometimes shave excision.
- Multiple or broad-based lesions can be treated by curettage with electrodesiccation, topical agents (trichloroacetic acid), or cryotherapy.
Actinic keratoses
- Multiple small flat or slightly elevated lesions
- Rough or scaly surface
- Variable pigmentation (red to yellowish brown to black)
- Caused by chronic sun exposure
- Most often seen in elderly, fair-skinned patients
- Malignant potential (15-20% become SCC); rarely metastatic
- Topical application of 5-FU, curettage with electrodesiccation, topical agents (trichloroacetic acid or phenol), or cryotherapy.