Dermatopathology part 1

Question 1

What is Vitiligo? What disease is it typically associated with?

Answer 1

Chronic depigmenting condition from complete loss of epidermal melanocytes

Associated with pernicious anemia and hasimoto’s thyroiditis.

Question 2

How does vitaligo cause depigmentation

Answer 2

Autoantibody against melanin concentration hormone receptor 1 in serum.

Presents on the 2nd or 3rd decades.

Higher in africans.

Question 3

Predilection of vitiligo

Answer 3

Acral areas and orifices.

Presents as asymptomatic white macules with sharp borders that gradually enlarge.

Hair will also lose pigments.

Can see the lesions better under a wood’s lamp.

Question 4

TX of vitiligo

Answer 4

slowly progressive, but 10-20% experience spontaneous regression.

some benefit with topical steroids, calcineruin inhibitors, and light therapy

Question 5

Freckle (Ephelis)

Answer 5

Basal layer hyperpigmentation

appear after sun exposure in lighhtly pigmented kids

darken with sun expsoure

no risk of malignancy

Question 6

Lentigo (lentigines)

Answer 6

Small (<1.0 cm) circumscribed brown macular lesions.

Hyperpigmentation of cells just above the basement membrane

unlike ephelides, lentigines do not darken with sun exposure.

Question 7

Lentigo histology

Answer 7

The rete ridges are elongated and appear club shaped or tortuous. Melanocytes are increased in the basal layer and melanophages appear in the upper dermis.

Question 8

Melanocytic nevi Gross features

Answer 8

tan to brown.

uniformly pigmented

small (usually <6mm in greatest dimension)

flat to elevated

well defined, rounded borders.

Question 9

melanocytic nevi histology

Answer 9

sharply defined

well nested at the dermal epidermal junction

melanocytes mature as they descend in dermis

no deep mitoses

no deep pigment in melanocytic nests

Question 10

Melanocytic nevi progression of maturation

Answer 10

junctional > compound > intradermal

Question 11

Junctional melanocytic neves

Answer 11

melanocytic nests at the dermal epidermal junction

nests restricted to the tips and sides of rete.

Question 12

compound melanocytic nevus

Answer 12

more raised and dome shaped than junctional nevus

histologic features of junctional nevus (intraepidermal nevus cell nets) + nests and cords of nevus cell in underlying dermis

as cells invade the dermis they mature and become smaller.

Question 13

Dermal melanocytic nevus histology

Answer 13

epidermal nests are lost completly

Question 14

spitz nevus description of what it presents cellularly

Answer 14

composed of spindle and/or epitheliod cells

dyskeratotic melanocytes (kamino bodies): eosinophilic bodies along dermal epidermal junction

sharply defined laterally

line symmetry from left to right

celfts separating nets from keratinocytes

Question 15

Sptiz nevus. Who get this and describe what it looks like

Answer 15

common in children

deep red color may be confused with hemangiomas

Question 16

Kamino bodies

Answer 16

eosinophilic collections of dyskeratotic melanocytes

Question 17

Spitz nevus location of the nests and caveats

Answer 17

netsts of melanocytes within the epidermis

nets are seperated from the epidermis by clefts

Question 18

dysplastic (atypical) melanocytic nevus description

Answer 18

commonly large, oval, and multiple

irregular pigment common

fading boarder or fried egg appearance (central papule, surrounding macule)

Question 19

dysplastic (atypical) melanocytic nevus Histologically

Answer 19

Histologic: usually compound, concentric papillary dermal fibrosis.

Question 20

dysplastic (atypical) melanocytic nevus nets

Answer 20

horizontally orieted nests with bridging of adjacent rete

nets are at the tips and sides of rete

cytologic atypia: hyperchromatic, enlarged nuclei

Question 21

Melanoma

Answer 21

1 cause of skin cancer deaths worldwide

malignancy of pigment producing cells (melanocytes which are derived from the neural crest)

develops de novo or from pre existing mole

found in the skin, eyes, GI tract, leptomeninges, oral and genital mucosa.\

4% of all skin cancers

Question 22

Verticle phase of melanoma

Answer 22

determiens tumor stage and this phase can lead to metastasis to lymph nodes, brain, GI tract, bone, liver and lungs most commonly

Question 23

Risk factors of melanoma

Answer 23

Changing mole

other things

Question 24

ABCDE rule of skin lesions

Answer 24

assymetry, border irregularity, color variation, diameter > 6mm, evolving

Question 25

radial growth phase

Answer 25

horizontal spread of melanoma cells within the epidermis and superficial dermis tumor cells lack the ability to metastasize

Question 26

verticle growth phase

Answer 26

tumor cells invade downward into deeper dermal layers as a mass cells with metastatic potential emerge invading cells do not mature as in melanocytic nevi grossly, a nodule appears

Question 27

superficial spreading

Answer 27

most common (50-75% of all melanomas) 25% from preexisting lesion sun exposed skin, typically on backs of men and lower legs of women but any age evolved lesions may show ultiple shades: red, tan, brown , blue, black, grey and white

Question 28

superficial spreading: histologic features

Answer 28

buckshot scatter of atypical melanocytes within the epdiermis (pagetoid spread) typically not symmetrical (R to L) Typically fails to mature from top to bottom deep mitoses may be present cytologic atypia

Question 29

Lentigo maligna 1 what gender typically gets it. Describe growth.

Answer 29

indolent, slow growing lesion typically, face of old men long radial growth phase, 10-50 years starts as tan brown macule, gradually enlarges, develops darker, asymmetric foci 5% of intraepidermal lesions evolve to become clinically palpable, signaling dermal invasion and transformation into lentigo maligna melanoma.

Question 30

Lentigo maligna 2 caused by, type of growth, and cell descrption

Answer 30

broad lesion on sun damaged skin predominantely junctional growth of atypical melanocytes cytologic atypia

Question 31

Lentigo maligna 3 distinguishing features

Answer 31

distinguishing features: malignant melona in situ. poorly nested and confluent melanocytes at the dermal epidermal junction. adnexal extension. Heavily sun-damaged skin (severe dermis solar elastosis)

Question 32

lentigo maligna melanoma

Answer 32

lentigo maligna with a vertical growth phase

Question 33

acral lentiginous melanoma

Answer 33

least common, < 5% of all melanomas most common melanoma in african americans adn asians palms, soles, beneath the nail plate hutchinson's sign

Question 34

nodular melanoma where on the body

Answer 34

15-30% of melanomas anywhere on the body can be amelanotic

Question 35

Nodular melanoma histo

Answer 35

vertical growth phase melanoma no apparent radial growth phase dermal growth occurs in isolation or occasionally, in association with an epidermal component mitoses are frequent and often atypical

Question 36

Breslow measurement

Answer 36

actual measurement of tumor most closely correlates with survival statistics

Question 37

clark level

Answer 37

not based on measurement, but on the number of layers of skin that the tumor has penetrated 1. epidermis 2. papillary dermis, not yet to papillary reticular junction 3. fills papillary dermis 4. reticular dermis 5. subcutaneous tissues

Question 38

Sentinel node biopsy

Answer 38

lymphoscintigraphy radioactive tracer and a gamma probe is used recommended for intermediate tumors (1 to 4 mm thickness) or high risk thin tumors minimally invasive technique that has been shown to help accurately stage the regional nodal basin with a lower associated rate of complications and costs compared to ELND subsequently full lymph dissection is performed if metastatic disease is present and adjuvant therapy like interferon alpha is administered

Question 39

prognostic factors

Answer 39

tumor thickness mitotic rate ulceration lymph node involvement satellite lesions distant metastases age: older the wrose gender: female have better prognosis anatomic location: upper extremities better than head, neck, trunk, +/- lower extremities