Flashcards in Management of Dysplastic Naevi not in 3rd Ed Deck (28):
The total number of melanocytic naevi and the presence of atypical moles are independent risk factors for the development of melanoma.
Most melanomas arise within dysplastic naevi.
F De novo.
Dysplastic naevi rarely occur on the chronic sun-exposed skin of the face or hands.
7% of Caucasians have clinically atypical (dysplastic) naevi.
Patients with >100 uniform small naevi are not at increased risk of melanoma.
F “Cheetah phenotype” – increased risk
Dysplastic naevus / atypical mole syndrome can occur sporadically or be inherited.
Unlike persons with common naevi, it is not unusual for persons with atypical naevi to continue to develop new lesions throughout life.
‘Classical’ atypical mole syndrome is characterised by having: >100 melanocytic naevi, 1/more naevi with atypical features, and 1/more naevi >8mm diameter.
Individuals with dysplastic naevi who have at least one blood relative with melanoma have a lifetime risk of developing melanoma of greater than 80%.
F At least two blood relatives.
Removal of all dysplastic naevi in a patient eliminates the risk of developing melanoma.
F Most arise de novo.
A wood’s lamp can help visualise areas of naevus regression by highlighting depigmented areas.
Proposed surgical margin for in situ melanoma is 10mm.
Proposed surgical margin for less than or equal to 1.0mm thick melanoma is 10mm.
Proposed surgical margin for 1.0-2.0mm thick melanoma is 10mm.
Proposed surgical margin for 2.01-4.0 mm thick melanoma is 20mm.
Proposed surgical margin for >4mm thick melanoma is 20mm.
Sentinel lymph node biopsies provide a survival advantage.
F Only provides prognostic information.
The incidence of a second primary melanoma is 25% in patients with a history of melanoma.
Risk factors that increase the chance of developing new primary melanoma(s) include male sex, older age, having atypical moles, family history of melanoma, and family history of atypical moles.
A focused review of systems aimed at pts with melanoma should include queries about weight loss, fatigue, headache, numbness, dizziness, SOB, cough, abdo pain and bone pain.
The first site of metastasis is most commonly the skin and subcutaneous tissue, followed by lymph nodes, lung, liver, brain and bone.
The greatest risk of recurrence of melanoma is in the first 10 years following the diagnosis.
F First 1-5 years.
The time to recurrence for patients with node-negative disease varies inversely with the thickness of the primary tumour.
T Thin melanomas can potentially recur many years after the initial diagnosis.
Regarding melanoma, men and older pts have a worse Px than women and younger pts.
Predictive factors for regional node metastasis include increasing tumour thickness, presence of ulceration, high mitotic index, lymphovascular invasion and Clark level greater than III.
Dysplastic naevi have increased recurrence rates
F 2014 questions – Dan added – this is how the question was remembered. I think false
Ophthalmology review is necessary in dysplastic naevus syndrome
F 2014 questions – Dan added