Wk 7 Melanoma Flashcards
Stages of melanoma
Stage 0: confined to epidermis
Stage 1: localized
What is Breslow depth?
Measurement in mm of depth of melanoma for staging
Melanoma growth patterns
Nodular -> greater mortality
What does survival w/ melanoma relate to most?
Lesion depth
-increased depth by mm -> higher T stage
Warning signs of melanoma acronym
Asymmetry
Border (irregular)
Color (multiple)
Diameter (>6 mm)
Evolving
Melanoma characteristics in darker skin types
What is ALM?
Acral lentiginous melanoma
Where does ALM appear most often on darker skin?
feet, nail beds, palms
-most common melanoma subtype
What are melanocytic nevi?
=Moles
benign neoplasms of melanocytes
-tend to arise in adolescence, peak by late 40s
-start at junction of epidermis and dermis
-w/ age become elevated, lose pigmentation, eventually regress
-junctional -> compound -> intradermal -> regression
Do nevi give rise to melanoma?
increase melanoma risk 2-4 fold
-nevus cells in 25-40% of melanomas
-.50% of melanomas arise de novo
Images of common melanocytic nevi
3 types of nevi
- congenital
- blue nevus
- halo nevus
Common nevi in darker skin
Examples of when to biopsy or not
Tricky b/c many have features of benign and malignant
3D melanoma detection
What is dermoscopy?
=multiple objective scoring system
-increased accuracy for experienced users, decreases for inexperienced
-NOT diagnostic but can increase confidence of dx
-can see deeper and diff structures of skin
What are signature lesions?
Characteristic patterns in some patients’ nevi
-does a given atypical lesion fit into a characteristic pattern?
-look for the ugly duckling lesion - the one that doesn’t fit with others= suspicious
What is seborrheic keratosis?
ABCD not sufficient
-warning sign of melanoma, but not melanoma
Compare evolving nevi and melanoma
Nevus - gradual change (no change month-to-month)
-maintains shape and pigment distribution, uniform darkening or lightening, uniform regression
Melanoma - rapid enlargement (>3 mm^2/ year), changes shape and pigment distribution, non-uniform darkening or lightening and regression
What is greatest increased risk for melanoma?
Family Hx (10-30x), approx 10% of melanoma patients
~33% of melanoma-prone families have germline variants in CDKN2A
What is the only way to document changes in nevi or melanoma?
Photography
-disadvantage - only monitoring known lesions
-most lesions de novo, so might miss new ones
What is the only way to document changes in nevi or melanoma?
Photography
-disadvantage - only monitoring known lesions
-most lesions de novo, so might miss new ones
What is diagnostic 2-GEP?
=Pigmented lesion assay
-tape-stripping
-collect cellular RNA from adhesive patch over lesions followed by quantitative PCR
-a 2 gene screening test for LINC00518 and PRAME
-both -> high risk (>90%)
-only one gene =moderate (10-50%)
-neither gene = low risk (1%)
Primary melanoma tx
Excision
-margins based on tumor depth
Primary melanoma tx
Excision
-margins based on tumor depth
How does immunotherapy work?
-utilize checkpoint inhibitors, which provide a negative signal to T cell so that it won’t kill a cell
-therapy provides a negative signal to the negative signal, allowing the T cell to kil the cell
What are the 2 phases of T cell activation?
- priming phase: anti-CTLA4
- Effector phase: anti-PD1
Driver mutations in melanoma
BRAF is most common (involved in RAS/MAPK pathway)
Targeted therapy for melanoma
-inhibits mutant BRAF
-resistance very common, side effects
-not given as first therapy (give immunotherapy first)
What is the best tx option for a patient w/ hx of mutant BRAF+ melanoma who develops distant metastases?
B. Immunotherapy
-BRAF inhibitor + MEK inhibitor = too toxic
-radiation not very effective for melanoma
