Melanoma Flashcards
What percentage of mucosal melanomas present
in the head and neck?
55%
What is the most common head and neck site
where mucosal melanoma is found?
Nasal cavity
Where do most melanomas arise?
● Most melanomas arise on the trunk and extremities.
● Nodular melanoma and lentigo maligna melanoma more
commonly occur in the head and neck than other
subtypes.
What is the incidence of lymphatic metastasis in
malignant melanoma?
Incidence varies by subtype, depth, and location.
● < 0.75 mm: < 5%
● 0.75 to 4.0 mm: 15 to 20%
● 4.0 mm: 34%
Incidence increases with ulceration, nodular type, Clark
level IV or V, and elevated mitotic rate.
What is the metastatic rate of desmoplastic
melanoma?
Pure desmoplastic melanoma displays regional lymph node involvement in 0 to 2.2% of cases, whereas mixed desmo-
plastic melanoma has regional lymph node involvement in 8.5 to 22%. Distant metastasis is similar in the two
subtypes, at approximately 11 to 12%.
How has the incidence of melanoma changed in the United States in the last 30 years?
● It has seen a threefold increase in the white population.
● The rate has been stable in the black population.
What are the risk factors for cutaneous
melanoma?
Family history, lightly pigmented skin, tendency to burn, red hair, DNA repair defects (e.g., xeroderma pigmentosum), chronic and intense sun exposure, equatorial residence, tanning bed use, immunosuppression, > 100 melanocytic nevi, more than five atypical melanocytic nevi,
multiple solar lentigines, personal history of cutaneous
melanoma
What familial autosomal dominant disorder
greatly increases the risk of melanoma?
Atypical mole syndrome
What are the common subtypes of cutaneous
melanoma?
● Superficial spreading (57%) ● Nodular melanoma (21%) ● Lentigo maligna (9%) ● Acral lentiginous (4%) ● Unclassifiable (4%) ● Other (5%)
What sizes of congenital nevus have an increased
risk of developing into melanoma?
Giant congenital nevus (2 cm or larger)
What is the most common histologic subtype of
melanoma?
Superficial spreading
What is the second most common histologic
subtype of melanoma and the most aggressive
subtype?
Nodular melanoma
What differentiates lentigo maligna from lentigo
maligna melanoma?
Lentigo maligna melanoma has invasion into the dermis.
What subtype of melanoma is found on the soles
of feet or palms of hands?
Acral lentiginous
Which melanoma subtype is considered the least
aggressive?
Lentigo maligna melanoma. It displays a long radial growth
phase relative to other subtypes.
What are the most common genetic aberrations
found in melanoma?
● Chronic sun-damaged skin: KIT > KIT + NRAS = BRAF =
NRAS
● Nonchronic sun-damaged skin: BRAF > > NRAS
● Mucosal: KIT > > NRAS
What are the ABCDEs of melanoma?
● A = asymmetry ● B = border irregularity ● C = color variability ● D = diameter greater than 6 mm ● E = evolving over time
What is the clinical evaluation that all patients with
newly diagnosed melanoma should receive?
Full-body skin examination, including hair-bearing areas and
intertriginous areas, and examination of the relevant lymph
node basins
When should imaging be performed in malignant
melanoma?
● Extensive primary (fixation, perineural symptoms)
● Abnormal or equivocal adenopathy
● Stage III or greater disease
● Specific signs or symptoms to suggest metastatic disease
What is the most ideal method to obtain a biopsy
of a lesion suspicious for melanoma?
Narrow-margin excisional biopsy with adequate depth to
determine accurate Breslow depth
What histopathologic markers are commonly used
to identify melanoma?
● Homatropine methylbromide (HMB-45)
● S-100 protein
● Melan-A (MART-1)
What is the preferred evaluation of suspicious
lymphadenopathy in patients with cutaneous
melanoma?
FNA with or without ultrasound. Equivocal adenopathy can
be evaluated with ultrasound. Suspicious adenopathy
should be biopsied. A normal ultrasound does not replace
sentinel lymph node biopsy.
What are potential sites for occult primaries in
patients with metastatic melanoma of the head
and neck?
Ocular, mucosal, external auditory canal, hair-bearing areas,
or tumor regression
Describe the Clark levels for melanoma staging.
● Level I: Epidermis only
● Level II: Through basal cell layer into papillary dermis
● Level III: Fills papillary dermis, to junction with reticular
dermis
● Level IV: Involves reticular dermis
● Level V: Subcutaneous tissue
