Atypical Melanoma – Written by Brittany Alce, PA-C

Malignant melanoma is the most dangerous form of skin cancer, and can present in a variety of ways. Frequently, melanoma presents as a new, dark spot on the skin with an irregular shape that continues to grow. However, not all melanoma presents this way, and it is important to know the variety of ways that melanoma can appear. Here are some examples of atypical presentations of melanoma:

Nodular melanoma:

Often symmetrical, dome shaped, regular borders, and usually one color. Elevated, Firm to the touch, and Growing are important signs to look for when evaluating new lumps or bumps on your skin.

Acral lentiginous and subungual melanoma:

Be sure to check your nails and under your feet when getting a manicure or pedicure! This type of melanoma presents as a new streak in a nail, a changing spot on the feet or hands, or an elevated, thick patch growing on feet or palms. It can be found on the palms, soles, under the nails, fingers and toes. Subungual melanoma is the most common type of melanoma in people with darker skin or of Asian descent and is a subtype of ALM. Subungual specifically refers to melanoma that can be found under the fingernails or toenails.

Desmoplastic melanoma:

Common on the head and neck, this type of melanoma tends to resemble scar-like lesions. They may be pigmented, but are usually skin-colored. These tend to be slow growing, so be sure to point out to your clinician any long-standing spots you may have noticed changing over time!

Amelanotic melanoma:

This type of melanoma presents with little to no pigment. These can present as skin-colored or red spots and can sometimes have faint pigment around the borders. They may not fall within the typical ABCDE criteria used to assess for any signs of melanoma due to lack of pigment and well or ill-defined borders. A good way to remember this rare form of melanoma is to think of the 3 R’s: Red, Raised, and Recent changes!