Melanoma Tests, Diagnosis, Prognosis and Stages

Early and accurate diagnosis is essential to melanoma care and successful treatment. At Banner MD Anderson Cancer Center, our team of skin cancer experts uses sophisticated pathology and imaging tests to ensure you get the right diagnosis and to personalize your care. 

What Screening Tests Are Available for Melanoma?

In addition to practicing sun safety, it’s important to do regular skin self-exams to find potential melanoma early. To do a self-exam, stand in front of a full-length mirror in a brightly lit room. Check all areas of your body, assessing any moles and lesions using the “A-B-C-D-E Rule.” Have another person check your scalp and back of your neck.

Consider photographing moles in question and see if they change over time. If you have many spots, regular screening is recommended. Annual screenings are also recommended if you have a fair complexion, blonde or red hair, freckles blue eyes and/or a tendency to sunburn, or if you have a history of using tanning beds.

If you’re at high risk for melanoma due to family history, many atypical moles or precancerous lesions (actinic keratosis) or past skin cancer, your doctor may recommend additional testing.

How Is Melanoma Diagnosed?

Most melanomas are brought to a doctor’s attention because a patient has noticed signs or symptoms. To verify melanoma, seeing a dermatologist (a doctor who specializes in the skin) is of the utmost importance. At Banner MD Anderson, our dermatologist will ask you questions about your medical history, do a physical examination and may perform a skin biopsy. If the skin biopsy results show melanoma, other tests may be done to determine if it has spread to other parts of the body, or you may be referred to one of our other specialists.

Melanoma Tests

• Dermoscopy: A handheld device that gives a close-up view of the skin using a powerful microscope and special light.
• Biopsy: In a biopsy, your doctor takes a small sample of tissue for testing in a laboratory. There are several types of biopsies your doctor may choose to do, including a: punch biopsy, excisional biopsy, incisional biopsy and shave biopsy. A biopsy will be able to diagnose and evaluate the melanoma’s thickness – the thicker the tumor, the more advanced the disease. To see if cancer has spread, your doctor may use a sentinel node biopsy (a lymph node dye test to test nearby lymph nodes).
• Imaging tests: X-rays, CT/CAT scan, MRI, PET scan and lymphoscintigraphy are used to see if the melanoma has spread to other areas of the body. These tests often are not needed for very early-stage melanoma.
• Genetic tests: Only about 10% of people who develop melanoma have a genetic risk factor. Talk to your doctor about genetic testing if several blood relatives have had melanoma.

What Is the Prognosis for Melanoma? 

In its early stages, melanoma is highly treatable – but it must be addressed quickly. If you ever see a new mole or a suspicious mark on your skin, have it looked by a dermatologist. 

According to the American Cancer Society, melanoma found in early stages can have up to a 98% survival rate. This year, it’s estimated more than 207,000 cases of melanoma will be diagnosed in the United States, of which about 101,000 cases will be non-invasive, confined to the top layer of skin (in situ).

Melanoma Skin Cancer Stages

Doctors use staging to identify if and how far skin cancer has spread. This is an important step in diagnosis as it helps your doctor determine what treatments will work best for you. Staging takes place after the diagnosis is confirmed and the type of melanoma is identified. Melanoma staging is based on tumor thickness, ulceration, location and spread to lymph nodes or other organs.

• Stage 0 (non-invasive melanoma or melanoma in situ): At the very beginning of the scale, cancerous cells are only in the outermost layer of skin (epidermis).
• Stage I (Stage 1): The tumor is less than 2 mm thick and may have ulceration. It has not spread.
• Stage II (Stage 2): The tumor is more than 2 mm thick and may have ulceration. The cancer has not spread.
• Stage III (Stage 3): The tumor can be any size and has spread to the lymph nodes or melanoma nodules can show up in the skin or dermis away from the primary tumor – this is called satellitosis (or melanoma with satellite lesions).
• Stage IV (Stage 4): The tumor can be any size and thickness and may be ulcerated. The melanoma has spread (metastasized) to more distant lymph nodes and/or other distant organs.