Seborrheic Keratosis

Common, appears 40+ yo. Tan to black macular, papular, or verrucous lesions that look "stuck on" Can be large and dark, don't confuse with melanoma.

Seborrheic Keratosis

Common, appears 40+ yo. Tan to black macular, papular, or verrucous lesions that look "stuck on" Can be large and dark, don't confuse with melanoma.

Dermatosis Papulosa Nigra

(Variant of Seborrheic Keratosis)

Common, multiple hyperpigmented papules on cheeks/face of African Americans

Stucco Keratoses

(Variant of Seborrheic Keratosis)

Gray/White papules on lower legs, ankles, feet. Pts can pick them off easily.

Sign of Leser-Trélat

Cherry Angiomas (Acquired Hemangioma)

Presentation:  Benign red to purple dome shaped papules up to 1 cm. Adult trunk and extremities, few to 100s.

Pathogenesis: Dilated capillaries and postcap. venules in upper dermis. May have hormonal stimulation b/c increase in pregnancy

Venous Lake

Dilated venules

Can be mistaken for melanoma but compressible

Common on ears & lips

Venous Lake

Pyogenic Granuloma

Presentation:

Reactive proliferating vascular lesion

Bright red to reddish-brown, usually pedunculated, friable nodule

Occurs in all ages but is more frequent in children and young adults. 

“band-aid sign”=tendency to bleed b/c most commonly in areas subject to trauma: hands, forearms, face, occasionally oral mucosa

Pathogenesis Unknown

Pyogenic Granuloma

Pyogenic Granuloma

Pyogenic Granuloma

Melanocytic Nevi

characteristics

Melanocytic Nevi

• A few nevi may be present in early childhood, increase in number until 20s and numbers decline with age
• Some relationship b/t number of nevi & sun exposure
• Familial inheritance pattern but the genetics not clearly defined.

Three types: Junctional, Compound, Intradermal

In general, they are well circumscribed pigmented or flesh-colored macules, papules or plaques found anywhere on the body.

• 1/3 of melanomas are associated with a pre-existing nevus
• Increase number of nevi correlates with an increased risk of melanoma.
• Diagnosed Clinically or with biopsy
• Benign appearing nevi=no Treatment needed
• “Dysplastic” or suspicious=Biopsy (bx)
• Small or medium congenital=monitor, bx prn
• Giant congenital=removal controversial

Junctional Nevus

flat discoloration

Compound Nevus

Tan, brown, red/brown papule with histologic components of both intradermal and junctional nevi. Hair growth common.

Intradermal Nevus

Flesh colored, pink, or tan/purple. Can also have hair like compund nevi.

Congenital Melanocytic Nevus

Brown papules or plaques, often hairy
Present at birth or by age 2.

Categorized based on size:

Small <1.5 cm

Medium 1.5 – 20 cm

Large/Giant >20 cm (when extrapolated to adult size) aka “Bathing Suit nevus”

risk of melanoma is between 5-7%

Usually develops early in childhood and almost always by age 20.

Melanoma is often deeper nodule, not on surface so frequent skin exams with palpation of the lesion is crucial

Congenital Melanocytic Nevus

Large/Giant >20 cm (when extrapolated to adult size) aka “Bathing Suit nevus”

risk of melanoma is between 5-7%

Usually develops early in childhood and almost always by age 20.

Melanoma is often deeper nodule, not on surface so frequent skin exams with palpation of the lesion is crucial

Atypical Nevi (Dysplastic Nevi)
“Nevus with Architectural disorder”

A controversial category, EITHER:

Nevus with morphologic changes that fit into the ABCDEs of melanoma

-OR-

A descriptive term for nevi with atypical cytology or architectural patterns on H & E.

Sporadic or familial

Usually on the trunk but can be anywhere on the body.

Few to 100s

Risk of melanoma is greater with a greater number of atypical nevi and for patients with a family history of melanoma:

between 2.1% to 8.8% increased relative risk of melanoma