Melanoma

Types

The four types of melanomas are Superficial spreading melanoma (SSM), Nodular melanoma (NM), Acral-lentiginous melanoma (ALM) and Lentigo maligna melanoma (LMM)

Superficial spreading melanoma (SSM) - It is the most common type of melanoma. An SSM usually first appears as a flat or slightly raised mark. It has a red, white and blue colour over a brown or black background and an irregular, notched margin. Initially, an SSM spreads through the epidermis. If not caught and treated at this stage, it eventually begins to grow into the dermis and may then spread to other parts of your body. SSM is commonly found on the trunk, upper arms, and thighs.

Nodular melanoma (NM) -This type of melanoma is flesh coloured with flecks of pigment around its base. NM usually appears as a small, round bump (nodule) with a smooth border. Most NMs are black, although some may be brown, blue, gray or even red in color. It can occur on any skin surface but is found more commonly on the trunk, upper arms, and thighs. NM spreads so rapidly, it is often quite advanced by the time it's diagnosed.

Acral-lentiginous melanoma (ALM) - ALM usually develops on the palms, soles or nails and is most common in dark-skinned races. It is normally brown or black with irregular borders. Because ALM is often mistaken for a minor problem, such as a bruise or blister, it may have penetrated deep into the underlying layers of skin before it's diagnosed.

Lentigo maligna melanoma (LMM). It is relatively rare and the lesions looks like a large flat freckle of tan, brown, black, whitish or slate colour and has irregularly scattered black nodules on the surface. LMM commonly develops under the fingernails, on the face and on the back of the hands. Generally they do not spread to other parts of the body. It may remain flat and confined to the epidermis for months to many years, but at some point will penetrate into the deeper levels of skin, increasing the potential for metastases.