What Is Mohs Surgery?

Mohs surgery, or Mohs micrographic surgery, is a special technique dermatologic surgeons use to remove skin cancer.

They shave very thin layers of tissue from the tumor site and look at each layer under a microscope. They repeat this process until all the cancer is gone.

With Mohs, your surgeon can remove cancer while sparing the healthy skin that surrounds the tumor (lesion).

UPMC offers Mohs surgery for many non-melanoma skin cancers. Our dermatologic surgeons specialize in removing and treating challenging tumors of the head and neck.

To learn more about Mohs surgery at UPMC or make an appointment, call 855-756-7768.

Your doctor may suggest Mohs surgery if you have:

  • Basal cell carcinoma (BCC).
  • Squamous cell carcinoma (SCC).
  • A large or deep skin tumor.
  • A tumor without clear edges.
  • Prior skin cancer that has returned (recurred).
  • Cancer in a place where there's a higher risk of recurrence (such as the face or hands).
  • Tumors in places where it's crucial to preserve healthy skin and minimize scarring (such as your face, eyelids, ears, or feet).

Doctors can cure skin cancer with Mohs in about 99% of people they treat. 

Mohs surgery offers many benefits for people with certain skin cancers. If it's right for you, your dermatologic surgeon can often remove all the cancer.

Mohs surgery also:

  • Preserves healthy tissue. Surgeons map the location of skin cancer and remove the smallest amount of skin possible. This helps reduce the risk of complications and scarring.
  • Reduces the need for anesthesia. Surgeons numb only a small spot around the cancer before removing tissue.
  • Means no hospital stay. Mohs surgery is an outpatient procedure, so there's no overnight stay needed. You'll spend the day in the doctor's office but go home to heal.
  • Improves accuracy of removing cancer. Checking each tissue layer helps ensure all cancer is gone before you go home.

Mostly, the risks of Mohs surgery are low.

Talk with your doctor about any health conditions you have that may increase your risk of:

  • Excessive bleeding.
  • Infection.
  • Scarring.
  • Poor wound healing.

Sometimes, the surgical wound may be larger than expected if the surgeon needs to remove more tissue.

You may also feel numbness or burning for a while after surgery if nerves get damaged.

Talk to your doctor about what you should do to get ready for Mohs surgery.

Tell them about any medications or supplements you take. Your doctor may want you to stop taking certain ones before Mohs surgery.

Plan to take your medications unless your doctor specifically tells you not to and follow all their instructions carefully.

Most Mohs surgery takes a whole day.

Ask your doctor if you can bring a family member or friend to keep you company while you wait for pathology results. Or you may want to bring a book or music to listen to while you wait.

Before Mohs surgery

When you arrive for Mohs surgery, your surgeon will:

  • Have you change into a hospital gown (if needed).
  • Find the skin cancer location and mark it with a pen.
  • Inject medicine to numb the skin around the tumor (local anesthetic) so you won't feel pain.

During Mohs surgery

Once the area around the cancer is numb, your surgeon will:

  • Use a scalpel to remove the visible tumor and shave a thin layer of tissue at the edges of the tumor (margin). You won't feel any pain.
  • Cover the area to keep your skin moist.
  • Look at the tissue using a microscope to check for cancer (pathology).
  • Talk with you about the results and remove the next thin layer (if needed).
  • Repeat this process until all of the cancer cells are gone.

After Mohs surgery

After confirming all cancer cells are gone, your surgeon may:

  • Leave a small wound open to heal on its own or close a larger wound with stitches.
  • Close a very large wound by covering it with tissue from somewhere else (skin graft or flap).
  • Apply a bandage to protect the wound as it heals.
  • Refer you to a plastic or an oculoplastic surgeon if the wound is very large or involves crucial eye structures.

Follow your doctor's instructions for how to care for the wound when you get home.

If you notice redness, swelling, or oozing at the wound — or if you get a fever — call your doctor right away.

Why Choose UPMC For Mohs Surgery?

Our fellowship-trained and board-certified dermatologic surgeons are experts in performing Mohs surgery.

We train other doctors in Mohs surgery techniques through our fellowship program. This extra training helps graduates develop expertise in removing challenging tumors and wound reconstruction.

Contact UPMC About Mohs Surgery

Call 855-756-7768 to make an appointment.