Melanoma Screening and Diagnosis

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If you have an abnormal-looking growth (lesion) on your skin that might be melanoma, your provider will:

  • Review and ask about your medical history and family history
  • Ask about your sun exposure, lifestyle, medicines and other risk factors
  • Ask about your symptoms, when the lesion first appeared and if it has changed in size or appearance
  • Perform a thorough physical exam and check the skin lesion, any other suspicious moles or marks and your lymph nodes 

Take Charge of Your Health

Talk to your primary care provider if you have symptoms that you think may be melanoma. UW Medicine Primary Care can help you get started. Learn about Fred Hutch's relationship with UW Medicine.

Melanoma Images

Learning what to look for on your skin is a great first step in protecting yourself from skin cancer. By becoming familiar with your own moles and how they change over time, you can spot potential problems early. This section provides a collection of melanoma pictures to help you understand what this type of skin cancer can look like.

Pictures of Melanoma Types

There are four basic types of cutaneous (skin) melanoma.

Bright red melanoma with rough edges

Superficial Spreading Melanoma

This picture shows the superficial spreading melanoma, the most common type of melanoma.

Black acral melanoma on the ball of a foot with rough edges

Acral Lentiginous Melanoma

This picture shows acral lentiginous melanoma, a type that spreads near the surface before growing deeper into the skin.

Lentigo melanoma on a cheek, dark brown with irregular edges

Lentigo Maligna

This picture shows lentigo maligna, a type of melanoma that stays close to the skin’s surface for a long time.

On a shoulder, a raised black round nodule

Nodular Melanoma

This picture shows nodular melanoma, a type of melanoma that grows into the dermis (the second layer of skin tissue) more quickly than other types do.

More About Melanoma Types

Use the “ABCDE” Guide to Spot Irregularities

Most people have some type of spots on their skin, whether they are freckles, birthmarks or moles. Most of the time, these spots are normal, but some may be precancerous or skin cancer.

The images in this section are early melanoma cancer pictures to help you see what you should look for. They show what a provider looks for when examining you, and also what you should look for during your monthly skin self-exams. Images courtesy of the Melanoma Research Foundation. 

common mole

A = Asymmetry

Common moles are symmetrical, but early melanomas are not. This means in early melanoma, if you drew a line down the center of a mole, the two halves will not look the same.

melanoma

B = Border

Early melanomas often have uneven borders, as shown in this melanoma picture. They may even have scalloped or notched edges.

common mole with shade

C = Color

Regular moles are usually a single shade of brown or black. But early melanomas are often varied shades of brown, tan or black, like in this melanoma picture where the left side of the mole appears darker than the right side. As early melanomas progress, red white and blue may appear.

early melanoma

D = Diameter

The diameter is the width of a circle across its center. The diameter of a melanoma is usually larger than a mole, though it can be smaller. Early melanomas generally grow to at least the size of a pencil eraser (about ¼-inch across).

E = Evolution

This means that there have been other changes to a mole or spot, but different from those already described.

How Is Melanoma Diagnosed?

Melanoma Biopsy

If your provider is concerned that a lesion might be cancer, they may recommend a melanoma biopsy. This involves taking a sample of suspicious tissue so a pathologist can examine the cells under a microscope in a lab to look for cancer cells. Common types of skin biopsies for melanoma detection include:

  • Shave biopsy: A sterile razor blade is used to shave off the lesion
  • Punch biopsy: An instrument called a punch is used to remove a circle of tissue from the lesion
  • Excisional biopsy: A scalpel is used to remove the entire growth

Sentinel Lymph Node Mapping and Biopsy

If you’ve been diagnosed with melanoma and your care team is wondering if the cancer cells have spread, your provider will want you to have a sentinel lymph node biopsy. In this procedure:

  • A tracer substance and a dye are injected near your tumor
  • The substance flows through lymph ducts to the first lymph node or nodes where cancer cells are likely to spread (sentinel nodes)
  • Your surgeon removes only the nodes where the substance appears
  • A pathologist checks the sentinel nodes for cancer

Imaging Studies and Lab Tests

Your provider might recommend other tests or scans to learn more about your melanoma diagnosis, especially if your tumor is deep or the cancer is in your lymph nodes. These may include a computed tomography (CT) scan, chest X-ray, positron emission tomography (PET) scan, magnetic resonance imaging (MRI) scan or bone scan, and tissue, blood or urine test.

Melanoma Screening and Diagnosis FAQ

Your provider might use an advanced tool like a dermatoscope, which is a handheld device that uses magnification and a special light to see structures and patterns within a mole. This can help your provider determine if your mole is noncancerous or if it’s suspicious, reducing the need for unnecessary biopsies.

If you have many moles or a history of melanoma, your provider might recommend a process called “mole mapping.” This involves taking high-resolution digital images of your entire body to create a baseline. Then, when you come back for visits, your provider can look at images from your previous visit and compare them to what your moles or spots look like now. Changing spots are a key indicator of potential problems.

The frequency of your future screenings will be determined by your provider based on your personal risk factors, such as having a high number of moles or a family history of melanoma. You should continue to perform monthly self-checks, paying close attention to the biopsied area and using the “ABCDE” guide to assess all of your moles for any changes. If you notice any suspicious spots or changes, contact your provider.