1.03 - Skin Cancer Flashcards
What are the layers of the skin?
Location of melanocytes.
Stratum basale of the epidermis.
Spread of melanoma.
- superficial horizontal spread
- vertical spread
- lymphatic spread
- haematogenous spread
Risk factors for melanoma.
- UV radiation
- moles
- lentigo maligna
- CDKN2A genetic mutation
- personal history of melanoma
- immunosuppression
What is lentigo meligna?
Melanoma in situ that consists of malignant cells but is not invasive. Increases the risk of malignant melanoma.
Patient education for malignant melanoma.
- UV protection (ie. avoid direct sunlight, avoid indoor tanning, wear suncream)
- skin-self examination
- ABCDEs of melanoma
ABCDEs of melanoma.
Asymmetry
Border irregular
Color variegation
Diameter >6mm
Evolving lesion
Patients should be advised to book urgent GP appointment if any mole shows any signs of the above.
What are the subtypes of melanoma?
- superficial spreading
- nodular melanoma
- lentigo malignant melanoma
- acral lengtiginous
Features of superficial spreading melanoma.
- most common melanoma (~65%)
- fits ABCDE criteria for diagnosis
- slow changes over years
- flat
Features of nodular melanoma.
- ~30% of all melanoma
- often found on back, check, head or neck
- raised or dome shaped
- darkly pigmented
British Association of Dermatologist suggest the following indications for referral.
- new mole appearing after the onset of puberty
- longstanding mole changing in shape, colour or size
- any mole with three or more colours
- any mole itching or bleeding
- new persistent skin lesion
- new pigmented line in nail
- lesion growing under the nail
Evaluation of skin lesions in clinic.
- dermoscopy
- biopsy
Laboratory tests for melanoma.
Lactate dehydrogenase indicates a worse prognosis if the cancer has metastasised.
Insensitive as a marker for metastatic disease and not usually clinically useful.
Imaging of melanoma.
- ultrasound (?lymph node mets)
- CXR (?baseline for future comparison)
- CT CAP (?staging)
- MRI (?spinal / brain mets)
- PET (?lymph node mets)
Factors that affect prognosis of melanoma.
Worse prognosis with:
- depth
- ulceration
- lymph node involvement
- haematogenous metastasis
- male sex
- young age
Treatment of melanoma.
- surgical excision with a wide margin
- immunotherapy
- targeted therapy
- radiotherapy
What is the role of melanin?
Produced in response to UV radiation exposure to protect against DNA damage.
Which parts of the body do melanomas most commonly affect?
Trunk or legs
Why do melanomas tend to metastasise earlier than other skin cancer types?
Vertical growth more common.
Genetic mutations associated with melanoma?
MAPK pathway
CDKN2A pathway
Increase the susceptibility to carcinogenic effects of UV radiation.
When does NICE recommend offering SLNB to patients with melanoma.
Breslow thickness >1mm without clinically apparent nodule of metastatic disease.
Staging of melanoma.
TNM
Genetic syndromes that predispose melanoma.
- familial atypical multiple mole melanoma syndrome (FAMMM)
What is the best prognostic factor for melanoma?
Breslow thickness at time of excision
