Malignant melanoma is a skin cancer with potential for metastasis to multiple body organs.
Melanomas are most common on trunk in men and on lower extremities in women.
Types of melanoma, in order of frequency, are:
- Superficial spreading melanoma – most common
- Nodular melanoma
- Letingo maligna melanoma
- Acreal lentiginous melanoma – least common
The British Association of Dermatology’s criteria for referring a mole to a dermatologist ?melanoma is:
- Mole which is changing in shape, colour or size
- Any mole which has 3 or more colours or has lost its symmetry
- A mole which is itching or bleeding
- A new pigmented line in a nail
- A lesion growing under a nail
Factors which suggest a lesion could be a melanoma are:
- Asymmetry
- Border irregularity
- Colour variation
- Diameter greater than 6 mm
Sun exposure and use of sunbeds increase risk of malignant melanoma.
Pregnancy and use of OCP do not increase risk.
Other factors identified to increase risk include:
- Moderately increase risk
- Previous primary melanoma
- Large number of moles
- Organ transplant
- 1 or 2 family members with melanoma
- Greatly increase risk
- Giant congenital pigmented naevus
- 3 or more family members with melanoma or pancreatic cancer
Prognosis is based on
- Breslow thickness = tumour thickness
- Clark level = histologic level of invasion
Metastatic disease has a poor prognosis. Chemotherapy of choice for metastatic disease is dacarbazine. This has no effect on CNS mets.
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