Melanoma Flashcards
What are the risk factors for malignant melanoma?
- Excessive UV exposure
- Skin type I
- History of >100 moles
- Atypical naevus
- Immunosuppression
- Family history
What are the clinical features of malignant melanoma?
- Pruritic
- Persistently bleeding skin lesions
- Asymmetry
- Irregular border with indistinct margins
- Irregular colour (2+ colours)
- Diameter >6mm
- Evolution of lesion (changes in size, shape, colour)
What are the different types of malignant melanoma?
- Superficial spreading melanoma
- Nodular melanoma
- Lentigo maligna melanoma
- Acral lentiginous melanoma
Which type of melanoma is most common?
Superficial spreading melanoma
What is the appearance of superficial spreading melanoma?
- Predilection for back or chest in men
- Predilection for extremities in women
- Flat, irregular tumour
- Sometimes with nodular segments
- Variable pigmentation
Describe the typical growth of a superficial spreading melanoma.
Relatively prolonged horizontal growth
What is the appearance of nodular melanoma?
- Predilection for back or chest in men
- Predilection for extremities in women
- Reddish-brown black, smooth nodules
- Verrucous surface or ulceration with bleeding
Describe the typical growth of a nodular melanoma.
Fast growth in depth
What is the appearance of lentigo maligna melanoma?
- Predileciton for sun-exposed skin areas
- Large and irregularly shaped patch
- Irregular pigmentation
Describe the typical growth of lentigo maligna melanoma.
Relatively slow horizontal growth
What is the appearance of acral lentiginous melanoma?
- Predilection for palms, soles, nailbeds, mucous membranes
- Irregularly shaped, brown-black pigmented macule
- Ulceration may occur
- Hutchinson sign of the nail in subungual type (dark linear patch, widens with time, arising from the nail)
Describe the typical growth of acral lentiginous melanoma.
Slow, horizontal growth
What investigations should be done when malignant melanoma is suspected?
- Full thickness excisional biopsy with 1-3mm margins
- Staging tests (USS or MRI) once diagnosis confirmed to determine tumour thickness, spread to lymph nodes, or distant metastasis
What staging system is used for melanoma, and what is this system based on?
- Breslow system
- Based on thickness (>4mm is stage 4)
How should melanoma be treated?
- Surgical excision (wide local excision done after the initial excision biopsy)
- Radiotherapy may sometimes be useful
- Chemotherapy for metastatic disease
