Frequently Asked Questions About Mohs Surgery

This information answers frequently asked questions about Mohs surgery. If you have a question that is not covered here, please talk with your doctor, physician assistant or nurse.

What is Mohs surgery?

Mohs surgery is a type of surgery to treat skin cancer. During the surgery, layers of cancerous tissue are removed and examined in the lab. These steps are repeated until all of the cancerous tissue is removed.

The goal of Mohs surgery is to remove the skin cancer, while doing the least amount of damage to the healthy tissue around the cancer.

Back to top

What are the advantages of Mohs surgery?

  • It is the most effective type of surgery to treat skin cancer.
  • Cancerous tissue is removed, but normal tissue is saved. This can reduce scarring.
  • It is an outpatient surgery, so you won’t be admitted to the hospital.
Back to top

What are the possible risks of Mohs surgery?

The most common risk of Mohs surgery is scarring at the surgery site. However, we will try to minimize it. Other possible risks of Mohs surgery include:

  • Slow or poor wound healing
  • Infection
  • Bleeding from the surgery site
  • Numbness at the surgery site
  • Regrowth of the tumor. This is more common with previously treated tumors and tumors that are large or have been on your skin for a long time.
Back to top

How do I prepare for Mohs surgery?

Your nurse will give you information on how to prepare for your surgery. He or she will review it with you.

We will call you 2 to 3 days before your surgery to confirm your appointment and answer any questions you have.

If you develop any illness (fever, cold, sore throat, or flu) or are hospitalized before your surgery, please call your doctor, physician assistant or nurse.

You may want to bring your lunch or a snack.  There’s a refrigerator available for your convenience.

Back to top

Should I bring someone with me?

Yes, we recommend that you bring a friend or family member with you. If this is not possible, tell your nurse.

Back to top

How long will Mohs surgery take?

It will take about 15 minutes to remove a layer of tissue and 60 minutes or more to process the tissue in the lab. If multiple layers need to be removed, you may have to spend the day at Memorial Sloan Kettering (MSK).

Back to top

Will I feel pain?

You will be given local anesthesia to numb the surgery site. You will be awake during your surgery, but you should not feel any pain.

Your doctor or nurse will ask about your pain and level of comfort before the removal of each layer.  If you do feel any pain, or discomfort during your skin surgery, please tell your doctor, physician assistant, or nurse.

Back to top

 What will happen during Mohs surgery?


  1. Your doctor or physician assistant will inject (give you a shot) local anesthesia into your skin to numb the surgery site.

  2. The cancerous tissue and a thin layer of surrounding tissue will be removed.

  3. A bandage will be placed on your wound and you will be taken to a waiting area.

  4. While you wait, you can relax and eat light snacks or your lunch.

  5. The removed tissue will be processed in the lab and your doctor or physician assistant will examine it.

  6. If cancer cells are found at the edge of the removed tissue, you will be brought back to your doctor or physician assistant’s office and a second layer of tissue will be removed.

  7. These steps will be repeated until there are no more cancer cells found at the borders (edges) of the tissue that is removed.

Back to top

What happens after all the cancer is removed?

After all the cancer is removed, you and your doctor or physician assistant will discuss the best way for your wound to heal and close. These include:

  • Allowing the wound to heal by itself.
  • Stitching the wound closed.
  • Creating a skin graft or flap to close the wound. A skin graft or flap is tissue that is taken from one part of your body and moved to the area of your body that needs to be covered.
  • Having a specialized surgeon close the wound.
Back to top

How do I take care of my wound?

Your nurse will give you written instructions and review them with you after your surgery.

Back to top

Will I experience pain after the surgery?

Most people don’t experience pain after Mohs surgery. If you have any pain or discomfort, you can take extra strength acetaminophen (Extra Strength Tylenol®).

Do not take aspirin or ibuprofen (Motrin®, Advil®). These medications make it harder for your blood to clot, which may increase bleeding.

Back to top

When will I need to see my doctor or physician assistant again?

You will need to see your doctor or physician assistant several times after your surgery. How often will depend on the size of the cancer and location of your surgery. Your doctor, physician assistant, or nurse will tell you when to schedule your appointments.

Back to top
If you have any questions or concerns, talk with a member of your healthcare team. You can reach them Monday through Friday from 9:00 am to 5:00 pm at ____________________. After 5:00 pm, during the weekend, and on holidays, please call____________________. If there’s no number listed, or you’re not sure, call 212-639-2000.
Frequently Asked Questions About Mohs Surgery
©2015 Memorial Sloan Kettering Cancer Center - Generated on July 31, 2015