What are the types of Melanoma?

This is the most common form of melanoma representing roughly 70% of all cases. This type of melanoma undergoes a long radial growth phase prior to invading deeper into the skin, reaching the dermis, and posing a threat of distant spread via the bloodstream or lymphatic system.

Superficial spreading melanomas are typically characterised by a lesion with irregular borders and uneven pigmentation.

Generally considered the least aggressive melanoma due to its long radial growth phase, Lentigo maligna melanoma is commonly found on older people who have worked in an outdoor occupation. These occur on areas of the body that have received a lot of sun exposure and are therefore most common on the face, ears, neck and head. This type of melanoma represents 5-10% of all melanomas.

This melanoma has a short horizontal growth phase. It is typically found on the soles of the feet, on the palms or under the fingernails. It is the most common form of melanoma in Asians and those with darker skin.This type of melanoma represents less than 5% of all melanomas.

Ocular melanoma is melanoma found in the eye, and is relatively uncommon, accounting for only 3% of all melanoma cases. It begins when melanocytes in the eye grow uncontrollably. There are two types of melanoma that occur in the eye; uveal (choroid, iris and ciliary body) and conjunctival (which occurs in the filmy white covering of the eye).

Intransit metastases are melanoma deposits within the lymphatic vessels located close to the site of the primary melanoma.  Up to 10% of melanoma patients develop intransit metastases between the primary tumour site and draining regional lymph nodes.