Nevi and Melanoma Flashcards
What cell type are melanocytes derived from?
• where can melanomas occur?
Neural Crest derivatives
Melanomas can occur ANYWHERE melanocytes migrate:
• Inner Ear
• Medulla
• Retina
• Skin
What is this?
• Key features?
Melanoma
Asymmetric lesion
Borders are notched
Color is irregular
Diameter greater than 6mm possible
Elevation present
Looks a lot like seborrheic keratosis but we see that it flattens into the dermis and lacks the stuck on appearance. It also lacks the fine keratin we would expect.
What determines your prognosis if you are diagnosed with melanoma?
Ulceration and Depth of dermal involvment is the most important factor to prognosis
What characteristics do nevi and melanomas have in common with respect to genomics and cellular composition?
• does having more nevi put you at a an elevated risk of melanoma?
Nevi and Melanomas;
• BOTH are composed of melanocytes
• BOTH share mutations like BRAF (so when you see BRAF mutation, don’t automatically jump to cancer)
Increase nevi to 50 or greater does incrase your risk of getting melanoma
T or F: Melanoma most often arises from a pre-existing nevus.
FALSE, most melanomas arise DE NEVO (only 1 in 5 if from a pre-exisiting mole)
What are the 5 general types of nevi?
- *1. Acquired melanocytic nevi
2. Halo nevi
3. Congenital nevi
4. Atypical (dysplastic) nevi
5. Other**
What are the 3 types of aquired melanocytic nevi?
• what are the differences among these?
- Junctional - located only in the basal cell layer of the EPIDERMIS (no dermal involvement)
- Compound - Present in both the DERMIS and EPIDERMIS
- Intradermal - only in the DERMIS
What is seen in each of these pictures?
Left: Junctional Melanocytic Nevus
Right: Compound Melanocytic Nevus
Bottom: Intradermal Melanocytic Nevus
What is this?
Common Acquired Melanocytic Nevus
(looks dermal to me, so probably doesn’t have color associated with it)
What is this?
Common aquired melanocytic nevus
How do the 3 types of Acquired malanocytic Nevi differ in gross appearance?
• how deep are they?
Junctional - 2-3mm in diameter
• Deeply pigmented and macular (flat)
• Arise at Dermal-Epidermal Junction ABOVE the basement membrane
Compound - 3-4mm in diameter
• Moderate Pigmentation and slightly raised
• Intraepidermal and intradermal mellanocytes
Dermal
• larger and dome shaped, witout brown color
• only in dermis
What is this?
Likely a Junctional Aquired melanocytic Nevus (flat and darkly pigmented)
What is this?
Intradermal Aquired Melanocytic Nevus
What is this?
Congenital Nevus
What are the Key Clinical Characteristics to look for in a congenital nevus?
• is their an increases risk of cancer?
Key:
• Pigmentation may range from brown to black with an irregular surface with hypertricosis.
Kids with LARGER lesions (greater than 20cm) are at a 5% risk of getting melanoma. Most often this occurs in the 1st 5 years of life.
What is the Single most important prognostic factor of whether melanoma will kill you?
LYMPH NODE INVOLVMENT = #1 most important prognositic factor
Breslow thickness is the most important histological prognositic factor
What is this?
Dysplastic Nevus
• differentate from seborrheic keratosis on the basis of it having that weird border that we never see in seborrheic keratosis.
Is this person at an increased risk of melanoma?
ONLY if they have lots of dysplastic nevi and a family history of melanoma
T or F: dysplatic nevus is part of a stepwise progression to melanoma
FALSE
What is the most Common Site of Melanoma Metastasis?
• what is the most common cause of Death related to melanoma?
**SKIN is the most likely place for melanoma to metastasize to
CNS involvment is what typically Kills patients**
What mutation is associated with a family history of dysplastic nevus syndrome and melanoma?
• are atypical precursors for melanoma?
CDNK2 (p16INK4A) Tumor Suppressor Gene
NO - atypical nevi are NOT precursors for melanoma
Pt. with multiple atypical nevi
What is shown here?
Dysplastic Nevus with Fried egg appearance (light raised center with dark rim)
Who is at the highest risk of getting melanoma?
• Among what age group is this the most common type of cancer?
Highest Risk: White Males over 50
Most Common type of Cancer in: 25-29 year olds
2nd most common in 15-29 year olds
What is this?
• Key features?
Melanoma:
Asymmetrical
Boarders are jagged and irregular
Color is pretty uniform BUT there is some gray in the center
Diameter - probably bigger than 6mm
Elevation/Evolution??
Is this a melanoma or a nevus?
• how do you know?
Melanoma during its radial growth phase = PAGETOID GROWTH
• Note that melanocytes appear with a clearing around them on histology
What is this?
• how do you know?
Melanoma in VERTICLE growth phase. You can tell this because we see pagetoid spread in the epidermis and verticle growth down into the dermis
**Note that this is big and blue like BCC but BCC will appear more nodular and will cleft away from surrounding tissue**
What are the ABCDEs of melanoma screening?
• what other 2 signs do we look for?
Do you think this is a melanoma?
This woman came in complaining about color change on this mole. What other features suggest malignancy?
- Irregular Border
- Its an ugly duckling
- Hx of recent color change
Do you suspect malignancy?
What subtype of melanoma is shown here?
• what classifies it as such?
Acral Lentiginous Melanoma
• Defined as melanoma on the subungual skin
In what population of patients is this melanoma most common?
Acral Lentiginous Melanoma
• most common in patients with darker pigmented skin
What type of melanoma is shown here?
Acral Lentiginous Melanoma
What is this?
Lentigo Maligna
What is shown here?
Melanoma in situ that has developed into an invasive lesion where the black raised lesion is seen
What is this?
Nodular Melanoma associated with Lentigo Maligna (melanoma in situ)
What subtype of melanoma is this?
• what characterizes this lesion?
• who most commonly gets this?
Nodular Melanoma - defined as melanoma with no preceding radial growth
• these are 2x as likely in men as women
Is this melanoma?
• If so what type?
• Key features?
This is SUPERFICIAL SPREADING MELANOMA
• Fails all of the ABCDE’s especially color
• This shows the “flag sign” where the lession looks red, white, and blue
Is this malignant?
• where does this usually show up?
• What would genetics look like on this?
Yes, this is a melanoma (shows flag sign)
• This is associated with UV exposed skin and BRAF mutations
What is this?
Seborrhiec Keratosis
• Notice that its shiny (hyperkeratotic)
• It almost looks like a scab that would pull off (stuck on appearance)
• Very symmetric
• Color is pretty uniform
What is this?
Melanoma (superficial spreading)
• Jagged Edges
• Looks less stuck on and more integrated into the skin
• Pretty asymmetric
• Color is a little bit inconsistent
What is this?
Seborrheic Keratosis
• Hyperkeratotic and Stuck on
What is this?
Seborrheic Keratosis (this looks very similar to Lentigo Maligna (melanoma in situ))
• Looks a little keratotic though
What is shown here?
Seborrheic Keratosis (temple), Melanoma in situe in center of forehead
What is this?
Melanoma
• More then 6mm
• Asymmetric
• Coloration is variable
• very irregular borders
What is this?
Melanoma with a halo around it indicating regression
What is this?
Acral Lentiginous Melanoma
What is this?
Melanoma with no pigment
Melanoma
BCC
What is this?
Melanoma of the iris
What is this?
METASTATIC melanoma
