Melanocytic Lesions - part 2 Flashcards
what percent of melanoma lesions are cutaneous?
91%
what are the high risk sites of melanoma?
BANS: back, arms, neck and scalp
what percent of high risk sites affected by melanoma is head and neck?
25%
other than cutaneous, what other sites can melanoma affect?
muscosa, ocular and other
how do you describe a melanocytic lesion?
ABCDE's: Asymmetry Border irregularity Color variegation Diameter >6 mm (size of pencil eraser) Evolving - enlarging or changing color
what are the growth phases of melanoma?
- radical
2. vertical
radial growth phase
spreads laterally
vertical growth phase
extends deeper into the CT
what is the precursor for melanoma?
lentigo maligna
what are the clinicopathologic types of melanoma?
- lentigo maligna melanoma
- superficial spreading melanoma
- nodular melanoma
- acral lentiginous melanoma
lentigo maligna (Hutchinson’s freckle)
melanoma in-situ
melanoma in-situ
melanoma in a purely RADIAL growth phase
type of people affected by lentigo maligna
older individuals with fair complexion
clinical feature of lentigo maligna
large macular lesion with irregular borders and UNEVEN pigmentation
how long does it take before vertical growth phase develops?
~15 years
what signals a previously flat lentigo maligna to enter the vertical growth phase and lentigo maligna melanoma?
nodularity in a previously flat lentigo maligna
histopathologic of lentigo maligna melanoma
nests of malignant melanocytes in epithelium and superficial CT
what is the most common type of melanoma?
superficial spreading melanoma
what does superficial spreading melanoma begin as?
a macule or plaque
clinical features of superficial spreading melanoma
starts off as a macule or plaque and exhibits classic clinical features (A, B, C, D’s and E)
superficial spreading melanoma sites
- interscapular area of men
2. back of legs on women
histopathologic of superficial spreading melanoma
- clusters of atypical melanocytes along basal layer and dropping into CT
- melanocytes invading epidermis producing pigment
T/F: nodular melanoma is a rapidly growing nodule
true, almost immediate vertical phase and little if any radial growth
clinical features of nodular melanoma
- usually deeply pigmented
2. amelanotic
amelanotic
melanocytes so poorly differentiated they can no longer produce melanin
what is the most common form of oral melanoma?
acral lentiginous melanoma
what is the most common form of melanoma in persons of color?
acral lentiginous melanoma
what type of melanoma is more aggressive than the cutaneous form?
acral lentiginous melanoma
what are the sites for acral lentiginous melanoma?
- palm of hands
- soles of feet
- subungual (under nails)
- mucous membranes
clinical features of CUTANEOUS acral lentiginous melanoma
- dark, may see color variegation
- irregular margin
- macule which develops into nodule
clinical features of ORAL acral lentiginous melanoma
- dark, may see color variegation
- can be amelanotic
- irregular margin
- macule which develops into nodule
- ± ulceration
- ± pain, usually if ulcerated
- soft to palpation
- cervical lymph node metastasis
T/F: there is a female predilection for ORAL acral lentiginous melanoma
false, male predilection
what age groups are primarily affected with ORAL acral lentiginous melanoma?
5th-7th decade
which site is commonly affected by ORAL acral lentiginous melanoma?
hard palate/maxillary alveolar mucosa
how does ORAL acral lentiginous melanoma appear on radiographs?
appears as irregular radiolucency or mixed lesion
treatment for melanoma
- surgical excision 1-2 cm margin for cutaneous lesions (lymph node dissection if needed)
- genotype-directed immunotherapy
- chemotheraphy, radiation have little impact but may be used
- close clinical follow-up
- SPF products
what is the prognosis of a ≤ 0.75 mm invasion?
96% 10 year survival
what is the prognosis of a > 3.6 mm invasion?
26% 10 year survival
who has a better prognosis for melanoma?
- younger than 50
2. female
which cutaneous site has a worse prognosis for melanoma?
trunk, head and neck (esp. scalp and neck)
T/F: melanoma has worse prognosis if the lesion was cutaneous rather than mucosal
false, worse for mucosal than cutaneous
why is the prognosis for oral melanoma poor?
because of difficulty achieving wide surgical margins and early metastasis
routes of metastasis for melanoma
- lymphatics
2. blood via brain, liver, bone
