While skin cancer may not cause any symptoms, some lesions may cause itching, bleeding, and tenderness. Any skin lesions that are new, change in size or color, or cause local symptoms should be evaluated by a physician.
When a person with a concerning skin lesion is seen by a doctor, the doctor will perform a history and physical examination. The doctor will ask questions related to the risk factors for skin cancer and will focus on specific changes in the lesion that is of concern. The physical examination will include a full body skin exam, as well as examination of any swellings in the neck, the underarm area, and the groin, which may indicate spread of the disease.
In order to diagnose skin cancer, a piece of tissue must be obtained. This is called a biopsy. For NMSC’s tissue may be obtained by shave, punch, or excision/incisional biopsy.
Shave biopsy: A shave biopsy is performed by using a scapel to remove the superficial skin layers. This is usually done for superficial skin lesions. The biopsy area is injected with numbing medicine and then the scapel is used to remove a tangential area of skin. This biopsy may not include all of the skin layers down to the fat layer. Shave biopsy sites are left open to heal and generally leave a small scar.
Punch biopsy: A punch biopsy is performed using a circular cutting device that takes out a cylinder of skin tissue. The biopsy device cuts through all layers of the skin using a circular motion down to the fat layer which is called the subcutaneous (below the skin) tissue. When performing a punch biopsy, a small amount of numbing medicine is injected into and around the lesion and then the core of tissue encompassing the lesion is removed. The skin defect is usually closed with 1 or 2 sutures. Punch biopsies are generally used in cases where the entire lesion may be removed by the punch biopsy device.
Excisional or incisional biopsy: An excisional or incisional biopsy is performed by using a scalpel (knife) to remove a sample of tissue. An excisional biopsy is generally used when the lesion is bigger than the usual punch biopsy devices but not so large that it will leave a large skin defect. An incisional biopsy is generally used for larger lesions when only a portion of the tissue is going to be sampled. In both cases, the biopsy area is injected with numbing medicine and then a piece of skin tissue is removed. As with the punch biopsy, the tissue sample will include all layers of the skin down to the fat layer. The biopsy site is then closed with several sutures.
Once a piece of the skin tissue is obtained, it is sent to a doctor who is specialized in looking at body tissues and can determine whether a skin cancer is present.