How Skin Cancer Is Found and Removed — At the Same Appointment

Mohs surgery removes most common skin cancers

Imagine walking into a doctor’s office in the morning with skin cancer. During the next few hours you undergo a procedure that removes and examines every bit of the cancer, all the while testing to make sure you are completely cancer-free. Then you drive home that afternoon.

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It happens every day. The procedure is called Mohs surgery, named for the surgeon who developed it in the 1930s.

Mohs surgery removes the skin cancer while preserving as much healthy tissue as possible, which is critical with cancers near the eyes, ears, nose, mouth, hands, feet and genitals.

The Mohs cure rate is spectacular for basal cell and squamous cell carcinomas, which are the most common skin cancers: 99% for basal cell, 97%  for squamous cell.

“The Mohs procedure ensures that the cancer is taken out with a high certainty of complete removal,” says dermatologist and Mohs surgeon Thomas Knackstedt, MD.

The procedure is the only method that evaluates 100% of the margins and is only performed by trained dermatologists, Dr. Knackstedt says.

The margin is the border of the tissue that is removed in cancer surgery, an important indicator of whether the cancer has been entirely removed.

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What happens during Mohs surgery

“You’re fully awake during the surgery and we explain the procedure and the involved steps in detail,” Dr. Knackstedt says.

First the site of the cancer is numbed, then the doctor quickly removes the cancerous tissue and a bit of the surrounding tissue. The area is mapped, and the tissues and margins examined microscopically by the doctor for cancer, all while you wait in the doctor’s office.

During the tissue examination, “there’s lots of downtime during which you can relax,” Dr. Knackstedt says. He recommends that patients bring a book or electronic device to pass the time.

What to expect after your procedure

If the margins are cancer-free, the surgery is complete and the wound is stitched up. If not, the process is repeated until the site is completely clear of cancerous cells.

A simple wound dressing is placed over the surgical area. Healing time is minimal, depending on the size of the wound.

“When they leave, patients say, ‘Wow, this wasn’t so bad.’ They’re pleasantly surprised at how straightforward it is,” Dr. Knackstedt says.

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Is Mohs surgery right for you?

Not all skin cancers need to be treated with a Mohs surgery.

Skin cancers are most common on the head and neck and often treated with Mohs, but those on the trunk and extremities are only treated with Mohs surgery under certain circumstances that your surgeon can determine, Dr. Knackstedt says.

Another kind of skin cancer called melanoma isn’t usually treated with Mohs surgery because it is biologically different from basal cell and squamous cell carcinomas, Dr. Knackstedt says.

Mohs surgery, though, is the single most effective technique for completely removing the most common kinds of skin cancer. Because the surgery can be accomplished relatively quickly with instant feedback on the success of removing the cancerous cells, the procedure brings many patients peace of mind Dr. Knackstedt says.

“It’s a really fabulous way of getting the cancer out — and the patient knowing it’s out,” he says.

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