Malignant Skin Cancer Flashcards
Most common form of cancer in US
Skin
skins cancers and people diagnosed annually
3.5 and 2 million respectively
Most common cause of BCC
UV radiation
In addition to UV radiation NMSC can also occur after (3)
ionizing radiation
arsenic
polycyclic hydrocarbon
Most common malignancy in US
BCC
BCC annually
2.8 million
BCC subtypes (4)
superficial (15%)
nodular (75%)
- micronodular
- pigmented (6%)
infiltrative (5%)
Sclerosing / morpheaform (3%)
The majority of BCC due to?
loss of function of PTCH1 which normally acts to block smoothened (smo) a transmembrane protein that accelerates growth
What is vismodegib?
an inhibitor of smoothened - used for the treatment of advanced BCC
Most common precacner affecting more than 58 million Americans?
Actinic keratosis
Actinic keratosis treatment?
cryosurgery (liquid N) Topical 5-fluorouracil Topical imiquimod Topical Diclofenac Photodynamic therapy Sun protection
Second most common malignancy
SCC
SCC occurs more often in
immunosuppressed
especailly organ translplant
risk factors SCC
UV damage thermal injury radiation HPV burn scars Marjlin's ulcer chronic injury (EB)
SCC subtypes (3)
SCC in situ (Bowen’s)
Keratoacanthoma
Invasive SCC
SCC can be induced by HPV –>
SCC in situ on genitals :)
SCC in situ means only in the
epidermis
Keratoacanthoma clinical features? - distribution - growth - size - appearance - complications
distribution - primarily sun exposed
rapid growth over 6-8 weeks
size 1-3cm
crateriform endophytic and exophytic nodule with central keratin plug
complications - deep invasion without regression in 10-20%
SCC
typical apperance?
hyperkeratotic papule with variable size and thickness
SCC
Local?
chronically sun damaged skin
SCC
metastasis?
0.3-5%
SCC
mestasis more common where?
lip (10-30%)
is metastasis more common in SCC or BCC
SCC
SC and transplant patients
SCC - 65X
BCC - 10X
Melanoma 3.4x
Kaposi’s - 84X
SC and transplant patients
risk factors
age / skin type / uv exposure
genetic
HPV (in 65-90% of SCC)
SC and transplant patients
level of immunosuppression and risk
cd4 count
meds
SC and transplant
more at risk tranplants?
heart>kidney>liver
Non transplant SCC:BCC
1:4
Transplant BCC:SCC
1:4
Does the risk of skin cancer increase or decrease with number of years post-transplant
incidence increases with number of years post-transplant
sun exposed more at risk (i.e. Australians vs Dutch)
NMSC treatment
Topical 5-fluoruracil Topical Imiquimod Cryosurgery Electrodessication and Curettage Excision Mohs micrographic surgery Radiation
Malignant melanoma ABCDE
A = Asymmetry B = Border irregularity C = Color variegation D = Diameter greater than 6 mm E = evolution (change)
fraction of melanoma arising from existing moles?
1/3
majority of normal moles have mutation in
BRAF
mutation that persists following malignant transformtion
BRAF
Increased risk MM fair skin
2-3
increased risk MM excessive sun
3-5
increased risk MM immunosuppression
2-8
increased risk MM first degree relative
2-8
increased risk MM whites
12
increased risk MM large congenital nevus (20cm)
17-21
increased risk MM sporadic dysplastic nevus syndrome
7-70
increased risk MM familial atypical mole and malignant melanoma
148
MM is the most common form of caner for which demographic / and second most common?
25-29 most common
15-29 second most
new cases and deaths
76,100 new
9,700 death
1/hr
MM lifetime risk overtime
has dramatically increased
MM only cancer _____
whose incidence is increasing anually
MM colorado year
1400
MM age group
all ages
53 median
MM
distribution
Blacks - acral and mucosa
men - back
women - legs / torso
MM variants (4)
superficial spreading 70%
nodular 15-30%
lentigo maligna 5%
acral letiginous 2-10%
Clark level vs Breslow depth
Breslow better predictor
What is Breslow depth
tumor invsion in mm
Clark levels I II III IV V
I Epidermis II papillary dermis III mid dermis IV reticular dermis V sub-cu
MM in situ treatment
surgical excision 0.5cm with sub-cu
MM
surgical excision with 1cm margin to fascia
MM >1mm treatment
surgical excision with 1-2cm margins to fascia with sentinel lymph node biopsy
can you have melanoma in eye
yes, ocular melanoma - refer to opthomology
Frequent mutations in melanoma
BRAF 50%
NRAS 20%
Kit 2%
GNAQ 2%
Which drug block BRAF?
vemurafenib
dabrafenib
MEK inhibitors
Trametinib
Cobimetinib
used in combo with BRAF
C-kit inhibitors
imatinib
nilotinib
Targeted immunotherapy for melanoma?
PD-1 inhibitors
CTLA-4 inhibitors
PD-1 inhibitors
immunotherapy melanoma
pembrolizumab
nivolumab
immune checkpoint blockade - many tumor cells express PD-L1 and immunosuppressive PD-1 ligand - inhibition of this action can enhance T cell anti-cancer acitivity
CTLA-4 inhibitor
ipilimumab
block ctla-4 receptor on t cells
allowing stronger immune response
skin cancer due tanning vs lung cancer and smoking
skin cancer may be higher
UVR is a proven human carcinogen and is classified as group 1 which includes ____________________
plutonium and cigerettes
one indoor tanning session increases risk of melanoma by
20%
after the first indoor tanning session each additional session increases risk by
2%
of melanoma cases among 18-29 year olds who had tenned indoors, what % were attributable to tanning bed use?
76
The 6 Ss of sun cancer avoidance
sun avoidance (avoid mid-day sun) sun protective clothing shade sunscreen sombrero sunglasses
SPF
Sun protective factor
screen UVB
What does it mean to have SPF 15
Prolongs burning time by a factor of 15 –> would take 15 times longer to develop a sunburn than without session
Whe should sunscreen be used?
every day to sun exposed skin - not just if going out in sun
do windows protect against UVR?
UVB not UVA
What % of sun UV rays pass through clouds
80%
sand reflects %
snow reflects %
sand 25
snow 80
When should sunscreen be applied?
15-30 minutes before going outdoors
how much sunscreen
1 ounce shotglass should cover exposed areas
how often should sunscreen be reapplied?
every 2 hours or after swimming/sweating
“water-resistant” sunscreen lose their effectiveness after ___ minutes in water
40
Kaposi’s sarcoma
endothelial cell malignancy HHV-8
Usually appears on skin or mucosal surfaces (mouth) but can also develop in lymph nodes / lungs / or GI tract
immunosuppressed
4 types of KS?
Classic
Lymphadenopathic
Iatrogenic
AIDS
Classic KS?
Mediterranean
occurs primarily in elderly emn on Eastern European descent - often lower leg?
Lymphadenopathic KS?
Endemic to Africa
Aggressive form primarily in equatorial Africa
Affects young men and is rapidly fatal
Iatrogenic KS
Transplant related
due to chronic immunosuppression
AIDS KS
Associated Epidemic
incidence is declining with better antivirals
KS therapy (4)
radiation
exicison
interferon
chemo
Stage IV melanoma treatment?
surgery radiation therapy immunotherapy targeted therapy chemotherapy
