DD 03-07-14 09-10am Skin Cancer slides - Dunnick Flashcards Preview

Unit 3 D&D > DD 03-07-14 09-10am Skin Cancer slides - Dunnick > Flashcards

Flashcards in DD 03-07-14 09-10am Skin Cancer slides - Dunnick Deck (49):
1

Skin cancer - prevalence

= most common form of cancer in US
Each year...
- >3.5 million skin cancers Dxed in >2 million ppl
- More new cases of skin cancer than combined incidence of breast, prostate, lung & colon cancers

2

Common Skin Cancer Types

Basal cell
Squamous cell
Melanoma

3

Non-melanoma Skin Cancer - Risk Factors

- Fair skin + geographic areas w/ high UV exposure
- UV radiation is most common cause of BCC
- Ionizing radiation, arsenic or polycyclic hydrocarbon exposure

4

Basal Cell Carcinoma - prevalence, morbidity/mortality

= Most common malignancy in the US
- ~2.8 million are Dxed annually in US
- rarely fatal, but can be highly disfiguring if allowed to grow

5

Basal Cell Carcinoma - Subtypes & prevalence

Superficial (15%)

Nodular (75%)
- Micronodular
- Pigmented (6%)

Infiltrative (5%)

Sclerosing / Morpheaform / Desmoplastic (3%)

6

Superficial BCC

?

7

Nodular BCC

?

8

Desmoplastic/Sclerosing/Morpheaform BCC

?

9

Pigmented BCC

?

10

Hedgehog Alterations in BCC & Treatment

Most BCCs have loss of function of PTCH1
= normally acts to block smoothened (SMO), a transmembrane protein

Vismodegib
= inhibitor of smoothened
= approved in 2012 for treatment of advanced BCC

11

Actinic Keratosis (AK) - defn., prevalence, lead to...

= Intraepidermal neoplasia
= most common pre-cancer affecting >58 million Americans
- ~65% of all squamous cell carcinomas & ~36% of all basal cell carcinomas arise in lesions previously Dxed as AKs

12

Actinic Keratosis - Treatment

Cryosurgery
- Liquid nitrogen (boiling point of -196 C)

Topical...
- 5-fluoruracil
- Imiquimod
- Diclofenac

Photodynamic therapy

Sun protection

13

Squamous cell carcinoma - prevalence

- 2nd most common cutaneous malignancy
- More common in immunosuppressed, esp. organ transplant pts

14

Squamous cell carcinoma - Risk factors

- UV damage
- Thermal injury
- Radiation
- HPV
- Burn scars (Marjolin’s ulcer)
- Chronic injury (i.e. EB)

15

Squamous cell carcinoma - Subtypes

- SCC in situ (Bowen’s disease)
- Keratoacanthoma
- Invasive SCC

16

Keratoacanthoma - distribution, time of growth, appearance

= subtype of squamous cell carcinoma

Distribution- primarily sun-exposed skin

Rapid growth over 6-8 weeks

Size- 1-3 cm

Crateriform endophytic & exophytic nodule w/ central keratin plug

17

Keratoacanthoma - Complications

Deep invasion w/out regression in 10-20%

18

Squamous Cell Carcinoma - appearance & distribution

Hyperkeratotic papule w/ variable size & thickness

Typically found on chronically sun-damaged skin

19

Squamous Cell Carcinoma - complications

Metastasis occurs in 0.3-5%
= more common in SCC of the lip (10-30%)

20

Types of Skin Cancer & Transplant Pts Risks

Kaposi’s sarcoma = 84 fold risk
SCC = 65 fold risk
BCC = 10 fold risk
Melanoma = 3.4 fold risk

21

Skin Cancer & Transplant Pts - Risk factors

Age, Skin type, UV radiation

Genetic Factors

HPV (in 65-90% of SCC)

Level of immunosuppression:
- CD4 count
- Medications
- Heart > Kidney > Liver

22

Skin Cancer & Transplant Pts - Statistics

Non-transplant pts SCC:BCC = 1:4
Transplant pts SCC:BCC = 4:1

Incidence of skin cancer increases w/ # of years post-transplant:
- 0.2-7% after 1 yr
- 47-82% after 20 yrs

23

Non-melanoma Skin Cancer - Treatment

Topical...
- 5-fluoruracil
- Imiquimod

Cryosurgery

Electrodessication & Curettage

Excision

Mohs micrographic surgery

Radiation

24

Malignant Melanoma - ABCD(E) & Ugly Duckling Guidelines

A = Asymmetry
B = Border irregularity
C = Color variegation
D = Diameter greater than 6 mm
(E = Evolution or change)

Ugly Duckling = if it looks different than other moles on the pt's body

25

Stages of the Progression of Melanoma

1. Benign Nevus
2. Dysplastic Nevus
3. Radial-Growth Phase
4. Vertical-Growth Phase
5. Metastatic Melanoma

26

Biologic Events & Molecular Changes in Progression of Melanoma - Benign Nevus Stage

- Benign limited growth
- BRAF mutation & Activation of mitogen-activated protein-kinase (MAPK) pathway

27

Biologic Events & Molecular Changes in Progression of Melanoma - Dysplastic Nevus Stage

- Premalignant
- Lesions may egress
- Random atypia
- CDKN2A loss (cyclin-dependent kinase inhibitor 2A)
- PTEN loss (phosphatase & tensin homologue)

28

Biologic Events & Molecular Changes in Progression of Melanoma - Radial Growth Phase

- Decrased differentiation
- Unlimited hyperplasia
- Cannot grown in soft agar
- Clonal proliferation
- Increased CD1

29

Biologic Events & Molecular Changes in Progression of Melanoma - Vertical Growth Phase

- Continued decreased differentiation
- Crosses basement membrane
- Grows in soft agar
- Forms tumor

Loss of E-cadherin

Reduction of Reduced TRPM1 (melastatin 1)
= melanocyte specific gene

Expression of:
- N-cadherin
- alphaVbeta3 integrin
- MMP-2
- Survivin

30

Biologic Events & Molecular Changes in Progression of Melanoma - Metastatic Melanoma Stage

- Continued decreased differentiation
- Dissociation from primary tumor
- Grows at distant sites
- Absent TRPM1 ---> associated w/ metastatic properties

31

Malignant Melanoma - Relative risk

Fair skin - 2-3
Excessive sun exposure - 3-5
Immunosuppression - 2-8
MM in 1st degree relative - 2-8
Whites - 12
Large congenital nevus - 17-21
Sporadic dysplastic nevus syndrome - 7-70
FAMMM - 148

32

Melanoma - Epidemiology

- ~76,100 new melanomas will be Dx
- ~9,710 ppl expected to die of melanoma
= most common form of cancer for young adults 25-29 years old
- 2nd most common form of cancer for young people 15-29 years old
- One person dies of melanoma every hour (every 57 minutes)

33

Age-standardized death rates in Melanoma

?

34

Malignant Melanoma - Statistics

- Rapidity of increase exceeds all malignancies except for lung cancer in women
- Of 7 most common cancers in US, melanoma is only one whose incidence is increasing (1.9% annually)

35

Colorado Cancers Statistics (Cases estimated for 2014)

All Cancer: 23,810
Female Breast: 3,780
Prostate: 3,680
Lung & Bronchus: 2,540
Colon & Rectum: 1,720
Melanoma: 1,400

36

Malignant Melanoma - Demographics

Affects all age groups
- Median 53 yo

Distribution:
- Blacks- acral and mucosa
- Men- back
- Women- legs (torso in females age 15-29, perhaps due to tanning)

37

Malignant Melanoma - Clinical Variants

Superficial spreading - 70%
Nodular - 15-30%
Lentigo maligna melanoma - 5%
Acral lentiginous - 2-10%

38

Breslow Depth

Tumor invasion in millimeters

39

Clark Levels

I Epidermis
II Papillary Dermis
III Mid Dermis
IV Reticular Dermis
V SubQ fat

40

Malignant Melanoma - Treatment

Surgical excision
- MM in-situ: 0.5 cm w/ SubQ tissue
- MM 1 mm: 1-2 cm margins to fascia w/ sentinel node biopsy

41

Mutations in Melanoma

Frequency of Mutations in Melanoma:
-BRAF 50%
-NRAS 20%
-Kit 2%
-GNAQ 2%

*Vemurafenib for BRAF V600E

42

Vemurafenib

- BRAF inhibitor

43

Malignant Melanoma and Tanning

- # of skin cancer cases due to tanning may be higher than # of lung cancer cases due to smoking

- UV radiation (UVR) is a proven human carcinogen, put in Group 1 (includes plutonium & cigarettes)

- Just one indoor tanning session increases risk of melanoma by 20%
- Each additional session increases risk 2% 

Of melanoma cases among 18-to-29-year-olds who had tanned indoors, 76% were attributable to tanning bed use.  

HB1054 Calls for a ban on tanning in Colorado <18

44

Skin Cancer Prevention

- Sun avoidance (Avoid mid-day sun)
- Sun protective clothing (Long-sleeved shirt)
- Shade
- Sunscreen
- Sombrero (Wide-brimmed Hat)
- Sunglasses

45

What is SPF?

= "Sun Protection Factor"
= only reflects product’s screening ability for UVB rays

Sunscreen w/ SPF 15 prolongs burning time by a factor of 15.
- i.e., it would take 15x longer to develop sunburn than w/out sunscreen

46

When should sunscreen be used?

- should be applied every day to sun exposed skin, not just if you are going out into the sun.
- Windows protect against UVB, but not UVA
- Even on cloudy days up to 80% of sun’s UV rays pass through clouds.
- Sand reflects 25% of the sun’s UV rays
- Snow reflects 80% of the sun’s UV rays

47

How much sunscreen should be used and how often should it be applied?

- Apply to dry skin 15-30 mins before going outdoors.
- 1 oz of sunscreen (shot glass) to cover exposed areas of body.
- Reapply at least every 2 hours or after swimming or sweating heavily.
- Even “water-resistant” sunscreens lose their effectiveness after 40 minutes in the water.

48

Will sunscreens limit amount of vitamin D I get?

- Individuals concerned about not getting enough vitamin D should discuss with their doctor the options for obtaining vitamin D through foods and/or a vitamin supplement.

49

Skin Cancer Prevention

Get Vitamin D safely through healthy diet
- may include vitamin supplements

Check your birthday suit on your birthday
- Self skin examinations
- See dermatologist if notice anything changing, growing or bleeding