Skin Cancer Screening and Diagnosis

A skin cancer screening can help identify skin cancer in its earliest stages while it’s easiest to treat. To detect and diagnose skin cancer, a dermatologist checks the skin over your entire body. He or she also asks questions about your past health and possible skin cancer symptoms you may have noticed, like a skin lesion that burns or itches without improvement.

Your doctor will use a bright light to examine your body for any atypical (unusual) moles or other changes in your skin. Some doctors may make what’s called a “mole map” to identify potentially cancerous moles and see if their appearance changes from year to year. Your doctor will also ask you questions about when your skin or mole appearance changes started, whether you have any family history of skin cancer and if you’ve had exposure to certain chemicals or substances.

If your doctor believes you might have skin cancer, you will need a skin biopsy. During a biopsy, your doctor removes a small sample of skin from the affected area. Next, a pathologist will examine the tissue under a microscope to look for cancer cells. The skin cancer treatment your doctor recommends will depend on the type of skin cancer identified and whether it has spread, so accurate screening and diagnosis is important.

More common skin cancers like basal cell carcinoma don’t usually spread, so your doctor may simply remove the entire growth during the biopsy without the need for more tests. However, if your biopsy shows melanoma, you may need surgery to remove surrounding tissue.

Depending on the results of the physical exam and biopsy, your doctor may also suggest additional imaging tests to verify a skin cancer diagnosis and whether the cancer has spread:

• Magnetic resonance imaging: MRI is a procedure that uses strong magnetic fields, radio waves and a computer to make detailed 3D pictures of areas in your body. For use in skin cancer screening, an MRI scan can show whether cancer has spread to nearby areas like the nerves. An MRI may also show if skin cancer has spread to internal areas of the body.
• Positron emission tomography scan: The PET scan uses a special camera to see organs in the body. The camera records a tracer (radioactive sugar) that your technician injects into a vein. Cancer cells use more sugar than normal cells, so the tracer shows up in the cancer cells. Your PET scan results can show if your skin cancer has spread to the lymph nodes or other areas of the body.