Bod: Dermatology: Non-Melanocytic Skin Cancer

Front 1

which skin cancers are the non-melanocytic type?

Back 1

Squamous cell
Basal cell

Front 2

c/c melanoma vs non-melanoma: risk of metastisis

Back 2

Low with non-melanocytic types

Front 3

Squamous cell carcinoma: characteristics

Back 3

- Arise from the upper layers of the epidermis

- Can metastisize and kill

Front 4

Basal cell carcinoma: characteristics

Back 4

- Arise from skin containig pilosebaceous units, probably from the lowest layer of epidermis

- Can be locally destructive and invade deep structures if neglected

Front 5

Elderly person: "I bumped my head 4 months ago and it just hasn't healed."

Back 5

Suspect SCC

Front 6

Basal cell carcinoma: clinical appearance

Back 6

Pearly, shiny, telangiectasias

"rodent ulcer" / "rodent-bitten" appearance

Front 7

Pigmented BCC can be confused with what?

Back 7

Melanoma

Front 8

Which types of UV radiation lead to skin cancer? What types lead to photoaging?

Back 8

UVB > UVA

UVA leads to skin aging

Front 9

Effects of UVA

Back 9

Wrinkling
Loss of elasticity
Lentigo
Telangiectasia
Mottled skin
Bruising

Histo:
dec prod of collagen
inc degredation of collagen
fragmentation of elastin
reduction in GAGs

Front 10

Defense against:
UVA
UVB

Back 10

UVA: biochromes (i.e. melanin) absorb UVA and transfer the energy to singlet oxygen producing radical oxygen.

UVB absorbed by the stratum corneum and minimizes deeper penetration

Front 11

SCC: pathophysiology

Back 11

- Cumulative UV exposure over time.

- Precusor lesions, tumor progression, metastisis

- Less aggressive than non-skin SCCs (cervical, oral , esophageal)

- Lips, genital, perianal confers higher risk

Front 12

What is the precusor lesion to SCC?

Back 12

Actinic keratosis

Front 13

Actinic Keratosis: clinical appearance

Back 13

- Multiple pink, red, light brown patches

- Sun exposed surfaces, often with surrounding telangiectasia, lentigines, dermatoheliosis

Front 14

Hypertrophic Actinic Keratosis

Back 14

Up to 50% of arms and hands go on to NMSC

Front 15

Actinic Chelitis: characteristics

Back 15

Lower lip
Important to rule out SCC since SCC of the lip has a high metastatic potential (16%)

Front 16

Squamous cell carcinoma: metastisis

Back 16

Uncommon (1/20)
More common in high risk tumors (lips,ears, genitals; large, poorly differentiated)

Mets go first to regional lymph nodes. Dissection can be curative

Front 17

Basal cell carcinoma: pathophysiology

Back 17

- Intermittant sun exposure is a risk

- Slow growing

- May ulcerate or bleed

- Ears, face, neck, trunk, extremities

- Invades locally

- Mets very rare

Front 18

Basal cell carcinoma: genetics

Back 18

PTCH (Hedgehog and Patched) control segmental polarity in embryonic development in flies, tumorgenesis

- PTCH is seen in Basal cell nevus syndrome patients

SCC (p53)
BCC (PTCH)

Front 19

Nevoid Basal Cell Carcinoma (Gorlin's) Syndrome: characteristics

Back 19

- AD
- PTCH mutation
- > 50% develop BCC (can have hundreds)
- Can be seen in younger persons (< 40)
- BCCs can look atypical

Front 20

Nevoid Basal Cell Carcinoma (Gorlin's) Syndrome: Clinical features

Back 20

- Pits on palms and soles
- Mandibular cysts
- Skeletal defects (osseous abnormalities of ribs, spine, skull)
- Partial agenesis of the corpus callosum
- Calcifications of the falx cerebri
- Medulloblastoma

Front 21

Xeroderma Pigmentosum: characteristics

Back 21

- AR
- Defective DNA repair
- Median age of first skin cancer: 8 y.o. (BCC, SCC)
- 2000x inc risk for melanoma
- 4800x inc risk for NMSC

Front 22

Epidermodysplasia verruciformis (EDV)

Back 22

Widespread HPV
33-50% develop SCC

Front 23

Recessive Dystrophic Epidermolysis Bullosa (RDEB)

Back 23

- Mutation in Collagen VII gene
- Chronic scarring
- SCC is #1 cause of death

Front 24

Oculocutaneous albinism

Back 24

Inc melanoma and SCCs

Front 25

What is the most common skin cancer in whites?

Back 25

BCC

Front 26

What is the most common skin cancer in blacks?

Back 26

SCC

Front 27

Non-melanocytic skin cancers: gender distribution

Back 27

M > F

Front 28

What toxin can cause non-melanocytic skin cancer?

Back 28

Arsenic!

Front 29

PUVA light therapy is associated with what cancer?

Back 29

With SCC

Front 30

Squamous cell skin cancer: SCC specific risk factor

Back 30

Carcinogens (arsenic, tar)
Chronic wounds, scars
HPV

Front 31

Pain with non-melanocytic skin cancer indicates what?

Back 31

May indicate invasion of nerves

Front 32

Which (SCC, BCC, melanoma) are appropriate to bx with a shave bx?

Back 32

SCC and BCC only

Not good for melanoma, because you need to get the full depth. Shave bx only gets the very top part of the dermis.

Front 33

Squamous cell carcinoma: clinical appearance

Back 33

Usually look pink or red and scaly

Genital or finger lesions may look more warty

Front 34

What are some SCC variants (6)

Back 34

1. In SITU (Bowen's Disease)
2. Erythroplasia of Queyrat
3. Verrucous carcinoma
4. Keratoacanthoma
5. SCC arising from a scar
6. Periungual

Front 35

Bowen's disease

Back 35

- Intraepidermal SCC
- Elderly white men
- Can occur anywhere on body
- Well demarcated, rough, scaly plaque

- SCC arising from SCC in SITU tends to be more aggressive than SCC arising from AK

- DDx: psoriasis, tinea

Front 36

Erythroplasia of Queyrat

Back 36

-SCCIS of the glans penis
-HPV 16, 18, 31, 35
-Most common in uncircumscribed men > 40
-Clinical: red, velvety, or smooth plaques

-DDx: psoriasis, irritant dermatits

-sexual partners need to be examined

Front 37

Verrucous carcinoma

Back 37

-a variant of SCC
-slow-growing, low grade tumor (mets rare, difficult to eradicate)

-early on can look like just a wart
-very deep

Front 38

Keratoacanthoma

Back 38

-SCC variant
-Crater-like in clinical and histologic appearance
-May resolve spontaneously
-Treat with excision

Front 39

SCC arising in a scar

Back 39

(Marjolin ulcer)

- high risk of mets

Front 40

Periungual SCC

Back 40

- Sx: erythema, swelling, pain
- Looks like a wart (if doesn't respond to wart txt, then should be biopsied)
- Assoc w HPV
- 3% risk of mets

Front 41

Lower lip SCC

Back 41

- Often preceded by actinic chelitis

- Smoking is a risk factor

- Mets in 10-15%

Front 42

Squamous cell carcinoma: Histopath

Back 42

- Irregular nests of epidermal cells invade the dermis

- Graded by degree of differentiation:
-Well diff
-Mod diff
-Poorly diff

Front 43

Basal cell carcinoma: clinical and histological subtypes

Back 43

1. Nodular (Classic)
2. Micronodular
3. Superficial
4. Infiltrative/Morpheaform

Front 44

Nodular BCC: characteristics

Back 44

- 50-80% of BCC
- Pearly, shiny papule with rolled borders
- Erosion, ulceration, crusting, bleeds, scabs
- Telangiectasias are common

Front 45

Superficial BCC: characteristics

Back 45

- 15% of all BCCs
- Trunk (45%), head and neck (40%), extremities (15%)

Clinical:
- Flat, scaly lesions
+/- atrophy, telangiectasias, ulceration
- Can get very large
- Most common BCC in HIV pts
- May be misdiagnosed as eczema, psoriasis, tinea

Front 46

Micronodular BCC: characteristics

Back 46

- 15% of BCCs
- Clinially can resemble nodular type, but histo shows smaller islands of tumor cells

Front 47

Infiltrative and Morpheaform BCC: characteristics

Back 47

- Higher risk types of BCC
- Have little "fingers" that extend into the dermis
- Can look like a scar
- Hard to cure with standard surgical excision

Front 48

Morpheaform (Sclerosing) BCC: characteristics

Back 48

- 4-6% of BCCs
- Looks like a scar (white or yellow, waxy, sclerotic plaque)
- Usually no ulceration or rolled border

Front 49

Basal cell carcinoma: histo key features

Back 49

- Dark blue/purple cells resembling basal layer cells

- +/- peripheral palisading

- Retraction (gap between tumor and stroma)

Front 50

Txt for actinic keratoses and superficial BCCs

Back 50

5-Flourouracil topical cream, Imiquimod cream

Also used off label for SCCIS

Front 51

What types of skin cancer is cryotherapy effective at treating?

Back 51

AKs
BCC, superficial
CSCC-IS

Front 52

Electrodessication and Curretage is the LEAST useful for cancers of what location? Most?

Back 52

The head and neck.

Most = forearms

Front 53

Mohs Micrographic Surgery

Back 53

- Used on tumors with contiguous growth

- Precise microscopic margin control of tumor margins (1-2 mm)

- Entire margin evaluated at the time of surgery, more taken from areas of margin that are still positive.

- 100% of peripheral and deep margin examined

- Highest cure rate (97-99%)

- Tissue conservation

- a little more expensive, takes a bit longer (4 hours)

- Tissue sparing

Front 54

"Traditional breadloafing" of a skin bx evaluates how much of the margins of a bx?

Back 54

< 1% !

Front 55

For > 60 y.o., BCC is more common in women, but SCC is more common in men

T or F?

Back 55

False: BCC is more common in both, but men are more likely in general to have SCC

Front 56

What is the most common skin cancer among organ transplant recipients?

A. Melanoma
B. BCC
C. SCC

Back 56

SCC (almost 100x more!)

Front 57

Which of the following are variants of SCC?

A. Bowen's Disease
B. Keratocanthoma
C. Actinic Keratosis
D. Verrucous carcinoma

Back 57

Actinic keratosis is NOT

Front 58

Seborrheic keratosis: histopath

Back 58

- Common benign epidermal tumor
- Any parts of body except palms and soles
- "Stuck-on" gray-brown, black growth
- Mimic melanoma, BCC

- Epidermal hyperplasia
- Pseudohorn cysts
- Uniform basal cells
- No cytological atypia

Front 59

Actinic karatosis: histopath

Back 59

- Sun-exposed area
- Ill-defined often multiple lesions
- Scaly erythematous macule

- Hyperkeratosis
- Parakeratosis
- Granular layers diminished
- cytological atypia in basal layer
- Dermal solar elastosis

Front 60

BCC: histopath

Back 60

- Palisading cells
- Retraction artifact

Front 61

SCC: histopath

Back 61

Invasion of dermis by atypical keratinocytes (hyperchromatic, pleomorphic, atypical mitoses)

Keratin pearls

Lichenoids and/or perivascular infiltrate