Finding a suspicious spot on your skin is a good reason to see your dermatologist. After examining your skin, your doctor will likely take a biopsy. This is a test that removes a small sample of the growth and sends it to a laboratory for further examination.

Biopsy results can either reassure you that the spot in question is benign (noncancerous) or let you know if it’s cancer so you can get started on treatment. For some basal cell and squamous cell skin cancers, a biopsy can remove enough of the tumor to eliminate the cancer.

Most biopsies can be done right in the doctor’s office using local anesthesia. Before the biopsy, the doctor or nurse will clean your skin. They may use a pen to mark the area that will be removed.

You’ll get a local anesthetic through a needle to numb your skin. The anesthetic might burn for a few seconds as it’s injected. Once it takes effect, you shouldn’t feel any pain during the procedure.

Dermatologists use a few biopsy methods to diagnose skin cancer. Here is what you can expect from each one.

A shave biopsy can be used to remove basal cell or squamous cell cancers that aren’t very deep. It’s not commonly used to diagnose melanoma.

After your skin has been cleaned and numbed, the doctor will use a blade, razor, scalpel, or other sharp surgical tool to shave off thin layers of skin. You won’t need stitches after a shave biopsy.

Pressure will be applied to the area to stop the bleeding. An ointment or mild electrical current (cautery) may also be applied to the biopsy site to stop the bleeding.

A punch biopsy uses a small circular blade that looks like a cookie cutter to remove a deep, round piece of skin. The blade is pushed down on the area of the lesion and rotated to remove the skin.

If the doctor removes a large area of skin, one or two stitches will be used to close the wound. Pressure is then applied to the site to stop the bleeding.

These biopsies use a surgical knife to remove tumors that are deeper in the skin.

  • An incisional biopsy removes a piece of the
    abnormal area of skin.
  • An excisional biopsy removes the whole area of
    abnormal skin, plus some of the healthy tissue around it. This type of biopsy
    is often used to diagnose melanoma.

The doctor will stitch the wound closed afterward.

The biopsy process takes about 15 minutes. After it’s done, the doctor will cover the wound with a sterile surgical dressing.

You’ll leave the doctor’s office with instructions on how to care for the surgical site. The wound might continue to bleed after the procedure. Put direct pressure on the wound to stop the bleeding. If you can’t get the bleeding to stop within 20 minutes, call your doctor.

You’ll need to clean the biopsy site and replace the bandage until your stitches are removed or the wound has healed. Some types of stitches need to be removed at your doctor’s office. Others will dissolve in about a week. Complete healing typically takes two weeks.

Your doctor will send the skin samples to a laboratory. There, a specialist called a pathologist will examine the cells to see if they are cancerous. Laboratories take a few days to a couple of weeks to complete the analysis of biopsy specimens.

Once the results are in, your doctor will discuss them with you. If you have cancer and your doctor was able to remove all the cancer cells, you should be all set. But if the pathologist found cancer in the outer edges of removed skin (the margins), your doctor will probably recommend that you undergo extra tests and treatment.

No matter which biopsy method your doctor uses, you will likely be left with a scar. Scars start out pink and raised, and then gradually fade. Ask your doctor about the potential for scarring with the procedure you’re having, and how to reduce the appearance of scars.