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Skin cancer diagnosis

​​​​​​​​Skin cancer is usually spotted by your dermatologist checking out a spot or bump on your skin.

An examination and possible testing will determine if the area​ is cancerous or some other issue.

The Dermatologists at Marshfield Clinic diagnose and treat all conditions and diseases of the skin.​

How is nonmelanoma skin cancer diagnosed?

Diagnosing skin cancer starts with checking out a bump, spot, or other mark on your skin.

Any area of skin that doesn’t look normal and may have disease is called a lesion.

You may need to see a dermatologist. This is a doctor with special training in diagnosing and treating skin problems. 

If your healthcare provider thinks you might have nonmelanoma skin cancer, you will need certain exams and tests to be sure.

Diagnosing skin cancer starts with your healthcare provider asking you questions. He or she will ask you about your health history, symptoms, risk factors, and family history of disease. Your healthcare provider will also give you a physical exam.

Make sure to tell your healthcare provider if you’ve had skin cancer in the past. Also tell him or her if anyone in your family has had skin cancer.

What is a biopsy?

A biopsy is a small piece (sample) of tissue that’s taken to be checked in a lab. Your healthcare provider will likely take a biopsy of any lesion that may look like cancer.

Types of biopsies

The different types of biopsies include:

  • Excisional biopsy. This type of biopsy is often used when your healthcare provider needs a wider or deeper piece of the skin. The entire lesion and part of the surrounding skin is removed. First, your healthcare provider uses numbing medicine on the area. Then the provider uses a surgical knife (scalpel) to remove a full thickness wedge of skin. The wound is closed with surgical thread (sutures), staples, tape, or surgical glue. What the provider uses depends on how large the incision is and where it is.

  • Incisional biopsy. This procedure is the same as an excisional biopsy. But only part of the lesion is removed.

  • Punch biopsy. This type uses a special tool to take a deep sample of skin. This may be done if the lesion is small or when just a part of a larger lesion needs more study. The tool removes a short cylinder of tissue, like an apple core. First, your healthcare provider uses a numbing medicine on the area. The punch tool is turned on the surface of the skin until it cuts through all the layers of skin. This includes the dermis, epidermis, and the most superficial parts of the subcutis (fat). The provider removes the biopsy sample and stitches together the edges of the wound. 

  • Shave biopsy. This type of biopsy removes the top layers of skin of a lesion. Your healthcare provider shaves off the layers with a scalpel. Shave biopsies are done with numbing medicine. Sometimes part of the lesion may be left behind. You may need another procedure to remove it completely. 

Lab tests of your biopsy sample

A biopsy sample is sent to a lab, where a doctor called a pathologist looks at them under a microscope.

If skin cancer is found, the pathologist will look at certain features of the lesion. These include the thickness of the lesion. This can help your healthcare provider figure out the extent (stage) of the skin cancer. The stage of skin cancer helps decide treatment options.

Getting your biopsy results

Your biopsy results will likely be ready in a few days to a week or so. Your healthcare provider will give you the results. He or she will talk with you about other tests that you may need if skin cancer is found. Make sure you understand the results and what follow-up you need.

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If this is a medical emergency, call 911.

Call: 1-866-520-2510

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How Much Do You Know About Melanoma?

Melanoma is a type of skin cancer. Although skin cancer is the most common type of cancer, melanoma cases make up less than 1% of all skin cancers, according to the American Cancer Society. Find out how much you know about melanoma by taking this quiz.

1. What is true about melanoma?
2. Melanoma often develops from which of these skin features?
3. Which of these may be a warning sign of melanoma?
4. Melanoma is most likely to be cured if:
5. The American Academy of Dermatology recommends wearing sunscreen when?
6. Sun protection factor (SPF) measures how a sunscreen is able to protect the skin from which of these?
7. What's an important part of the body to protect with sunscreen?
8. Although melanoma occurs mainly on the skin, where else can it start?