Skin Path (Gomez) Flashcards

Question

Blue Nevus

Answer 1

Intradermal, roughly wedge-shaped and slightly raised skin surface Thin, delicate * melanocytes in a dense reactive fibrotic stroma Melanin pigment in melanocytes, melanophages, or other adjacent structures cause the bluish color Benign with no significant risk for development of melanoma

Answer 2

Usually in children and young adults red or brown can mimic a melanoma (clinically and histologically) Characteristic raining down melanocyte pattern and Kamino bodies (eosinophilic amorphous globules)

Answer 3

* Involuting (regressing) nevus with extensive * lymphocyte infiltration and depigmentation of surrounding skin

Answer 4

Gross appearance is worrisome for melanoma Asymmetric Border irregular Color uneven Diameter > 6 mm Occur on non-sun or sun exposed skin Melanocyte nests at the tips of rete ridges * Rete ridges are often “bridged” (connected at their bases) * Reactive fibrosis of papillary dermis ``` Two forms Sporadic: not prone to malignancy Familial dysplastic nevus syndrome - Autosomal dominant - * 50% chance of melanoma by age 60 ```

Answer 5

Subtypes * Lentigo maligna (in situ sun exposed area) * Lentigo maligna melanoma (invasive lesion similar to lentigo maligna) * Superficial spreading (invasive, mostly horizontal growth phase) * Nodular (invasive, mostly vertical growth phase) * Acral lentiginous (palms, soles and subungual; non-caucasian; in situ or invasive) May occur in any skin location and occasionally in the eye, mucous membranes of the genitalia, anus, oral cavity, or other sites Most melanomas occur in sun damaged skin (also occur in non-sun exposed skin) - Occurs * primarily in adults; beginning in 3rd decade - * 90% originates de novo (isolated non-syndromic lesion) Can arise in or adjacent to a pre-existing melanocytic nevus - * Aggressive malignancy that metastasizes widely with significant mortality* --- Metastasizes to regional lymph nodes, liver, lungs, and brain

Answer 6

Caucasians with * fair skin - Albinism or genetic syndrome such as xeroderma pigmentosa dramatically increases incidence (50X-100X) Prolonged MCB * UV exposure * 3 episodes of “peeling” or severe sunburn before age 20 * Male gender Increased telomerase activity from mutated * TERT gene is present in 70% of skin melanomas but not routinely clinically tested 10% to 15% of melanomas are familial BRAF and NRAS mutations are also present in benign melanocytic nevi and are not sufficient for malignant transformation

Answer 7

Proliferation: P16 inhibition is inhibited by CDKN2A mutations; CDK4 mutations block p16 inhibition

Answer 8

A = Asymmetry Melanoma if lesion bisected & halves not identical B = Border irregularity Melanoma if the border is uneven or ragged C = Color variation Melanoma if more than one shade of pigment D = Diameter- Melanoma if diameter greater than 6 mm

Answer 9

Best prognostic indicator on skin biopsy is Breslow level (thickness from epidermal granular layer to deepest dermal penetration) 10 year survival: 92% for melanoma < 1.00 mm thick; 80% if 1.01 to 2.00 mm Melanoma survival depends on stage: Melanoma metastatic to lymph node(s) represents regional disease (II/III); any distant metastasis is stage IV.

Answer 10

solar elastosis solar lentigo actinic keratosis

Answer 11

Permanent, incremental damage to reticular collagen (elastosis) Loss of normal skin texture (leathery and wrinkled)

Answer 12

Focal autonomous overproduction of melanosomes +/- mild melanocyte hyperplasia

Answer 13

Neoplastic precancerous proliferation of keratinocytes - Does not involve full epidermal thickness - Size of lesions varies Erythematous, reddish-brown macules or minimally elevated papules - Increased keratin production (scaling) - Dermal increase in vascularity (redness) Middle-aged and elderly individuals - Face (particularly forehead), neck , dorsum of arms and hands, lips (actinic cheilitis) Usually asymptomatic, may have mild tenderness

Answer 14

Solar Keratosis, Senile Keratosis & Keratinocytic Intraepidermal Neoplasia

Answer 15

Malignant neoplasm of the basal regenerative epithelium of the epidermis - Malignant keratinocytes resemble maturing squamous cells - The malignant keratinocytes penetrate past the dermal-epidermal junction basement membrane (potential for metastasis) * * Exception: SCC in situ (e.g. Bowen disease, penile erythroplasia of Queyrat) * Epidemiology: Second most common cutaneous malignancy (#1 is basal cell carcinoma) Incidence increases with increasing age M>F * Primary etiology in sun exposed skin - * Long term sun exposure Immunosuppression increases incidence of invasive SCC - SCC of skin occurs in 40-70% in organ transplant recipient patients - Increased incidence with HIV

Answer 16

``` * Human papillomavirus (HPV) Chronic skin inflammation, ulcers and draining * fistulous tracts (osteomyelitis) Some dermatoses Burns Ionizing radiation Chemical exposures - Tars → * scrotal cancer in chimney sweeps - Arsenic ingestion - Tobacco and betel nut usage ``` Genetic syndromes - * Epidermodysplasia verruciformis (predisposition to HPV infections and HPV subtypes 5 and 8 can lead to SCC) - * Xeroderma pigmentosa (nucleotide excision repair pathway defects) - Other syndromes

Answer 17

Areas of greatest cumulative sun exposure Early invasive SCC is usually a small, firm, skin-colored or erythematous nodule with indistinct margins Surface may be smooth, verrucous, ulcerated, papillomatous or granular and may bleed easily Older SCCs are larger, invasive, and may be ulcerated Mortality is low for SCC of skin

Answer 18

Better term * “Squamous cell carcinoma, Keratoacanthoma type” Variant of invasive SCC Occurs on sun-exposed area M>F * Rapidly growing (days-weeks) * Often involutes and clears spontaneously within 3 to 4 months

Answer 19

Previously known as “basal cell epithelioma” Malignant neoplasm of the basal regenerative epithelium of the epidermis Malignant keratinocytes resemble squamous cells of the basalis layer Almost never metastasizes Numerous subtypes - Nodular and sclerosing types - - Have local invasion and destruction of adjacent dermis - - Tend to occur in hair-bearing skin subjected to sun exposure - Sclerosing and multifocal superficial spreading types - - Have difficult to identify margins - - Have high incidence of post resection recurrences Etiology Increased sunlight exposure in childhood and adolescence, and chronic exposure during adulthood

Answer 20

(Gorlin Syndrome) ``` Multiple basal cell carcinomas before age 20 Pits of the palms and soles Odontogenic keratocysts Medulloblastomas Ovarian fibromas ``` * Autosomal dominant disorder with * PATCH1 * gene mutations - SMO is normally inactive via PATCH1 function - When hh (sonic, Indian and Desert) proteins bind to PATCH1, SMO is activated leading to production of transcription factors (GLI1) that drive gene activation - PATCH1 mutations in Gorlin syndrome bypass the hh protein needed for SMO activation and SMO is active in the absence of hh proteins

Answer 21

85% occur on head and neck Remainder predominantly on trunk/limbs * Clinical appearance related to histologic type ** Rodent Ulcer = advanced presentation Most common cutaneous neoplasm (but is ignored in cancer data statistics) 98% occur after age 40 After age 50, 1% of population develops BCC each year M ~ F Almost all individuals with a significant history of face/neck sun exposure will develop one or more BCCs

Answer 22

Traditional or “classic” appearance of BCC Dome-shaped, * pearly papule or nodule Prominent surface * dilated dermal vessels (telangiectasia) May become quite large if neglected Easily treated by excision

Answer 23

Typically waxy yellowish-white or pearly white, indurated plaque that may retract below plane of skin surface Occurs predominately on face Poorly defined margins (edge of lesion) - Difficult to excise, high recurrence rate and may disfigure - * Mohs surgery can be used during excision to determine complete excision

Answer 24

Multifocal erythematous, scaly plaque; elevated rolled edges Occurs on * non-sun exposed skin sites on proximal limbs or trunk Multifocal growth pattern localized to dermal-epidermal junction - Part of a "field defect" and therefore can recur after excision Do not become locally invasive or metastasize If pigmented may be confused clinically with melanoma

Answer 25

Malignant * superficial fibroblastic neoplasm (fibrosarcoma of skin) Locally aggressive but rarely metastasizes * Bednar tumor is pigmented variant

Answer 26

Mycosis Fungoides CD4+ T-cell lymphoma of the skin (CLA, CCR4 & CCR10) Aggressive neoplasm with median survival 8-9 years (M>F) Phases - * Inflammatory erythrodermic pre-mycotic patch - * Plaque - * Tumor * Sezary syndrome is variant in which skin involvement is manifest as a * generalized exfoliative erythroderma Leukemic phase with * Sezary cell (cerebriform nuclei) seen in Sezary syndrome and 25% of plaque and tumor phases with survival <3 years

Answer 27

Darier sign – stroking of the skin leads to histamine release which causes swelling, erythema and edema Mast cell granules can be highlighted with toluidine blue or Wright-Giemsa stains