Skin Cancer (Non-Melanoma): Diagnosis

Approved by the Cancer.Net Editorial Board, 12/2016

ON THIS PAGE: You will find a description of the common test doctors use to find out whether a suspicious mole, slow-healing sore, or other skin feature is cancerous. To see other pages, use the menu.

Doctors use many tests to find, or diagnose, cancer. They also do tests to learn if cancer has spread to another part of the body from where it started. If this happens, it is called metastasis. Doctors may also do tests to learn which treatments could work best.

For most types of cancer, a biopsy is the only sure way for the doctor to know whether an area of the body has cancer (see below). Your doctor may consider these factors when choosing a diagnostic test:

  • The type of cancer suspected

  • Your signs and symptoms

  • Your age and medical condition

  • The results of earlier medical tests

Biopsy

Because non-melanoma skin cancer rarely spreads, a biopsy is often the only test needed to diagnose and find out the stage, or extent, of cancer. A biopsy is the removal of a small amount of tissue for examination under a microscope. During this procedure, the suspected skin lesion is removed, usually after a local anesthetic helps numb the area. The doctor also removes an area of healthy tissue around the lesion, which is called the margin.

The sample removed during the biopsy is then analyzed by a pathologist who determines if it is a skin cancer. A pathologist is a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease.

Your doctor will review the results of the biopsy with you. No further treatment beyond the biopsy may be necessary if the entire cancer was removed. However, if cancer cells were found in the margins of the removed tissue, additional treatment will usually be recommended.

Learn more about how a biopsy is used to make a diagnosis

The next section in this guide is Stages. It explains the system doctors use to describe the extent of the disease. Or, use the menu to choose another section to continue reading this guide.