SIU School of Medicine

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Division of Dermatology

Mohs Micrographic Skin Cancer Surgery

What is Mohs Micrographic Surgery?

Micrographic surgery is a very specialized way of treating skin cancers. It offers the highest possible cure rates while removing as little normal skin as possible.

Micrographic surgery is also called Mohs surgery in honor of Dr. Frederick Mohs who developed the technique.

The procedure begins by thoroughly numbing the area with a local anesthetic. Then all visible cancer is removed and a very thin layer of surrounding skin is taken to check for any remaining cancer cells that are otherwise invisible to the naked eye. This layer is processed by a technician and examined under the microscope by the micrographic surgeon. The location of any remaining cancer is carefully mapped on a diagram of the surgical wound and then removed in a thin layer. This tissue is also examined under the microscope and the process is repeated as often as necessary until all the cancer cells have been completely removed.

By using these techniques, the micrographic surgeon is able to locate and remove even the smallest cancer roots without taking large and unnecessary amounts of normal uninvolved skin.


What are my chances for cure?

Micrographic surgery offers the highest available cure rate of all skin cancer treatments. Over 96% of skin cancers are cured following micrographic surgery even if other treatments have failed. 99% are cured if the cancer has not been treated before. Other methods of treatment average only a 60-85% chance of cure if previous treatments have failed.


Will I be hospitalized?

No. Micrographic surgery is an outpatient office procedure and you will be able to return home the same day.


What happens on the day of surgery?

Your appointment will be scheduled early in the day. Our staff will escort you into a surgical suite where the surgeon will numb the area around the skin cancer. Once it is numb, the visible cancer and a thin layer of tissue will be removed. This tissue is carefully mapped and coded by the surgeon and taken to the adjoining laboratory where the technician processes the microscope slides. You will have a temporary dressing placed over the wound and will be free to return to the waiting room.

The surgical procedure usually takes only 10-15 minutes. However, it takes a minimum of 1-2 hours in the laboratory to process and examine the tissue. You will be asked to wait in the waiting room while the laboratory work is being done. If remaining cancer is found, you will be brought back to the surgical suite and a second thin layer will be taken from that area. This will also be taken to the laboratory for processing while you wait. Although there is no way to tell before surgery how many stages will be needed, most cancers are removed in three stages or less.

The hardest part of the procedure is waiting for the results from the laboratory. We would like to make the time you spend with us as pleasant and comfortable as possible. You may want to bring reading material to occupy your time. Magazines, coffee and vending machines are available near the waiting room. If your visit extends through the lunch hour, you or your companion may wish to visit the hospital cafeteria and bring you back something to eat since you are asked not to leave the waiting area until all surgical procedures are completed, unless otherwise instructed by our staff.

Since we do not know in advance how much time will be needed to remove the cancer and repair the wound, we ask that you make no other commitments for the entire day of your surgery.


Will the surgery leave a scar?

Yes. Any form of skin cancer treatment will leave a scar. However, because micro-graphic surgery removes as little normal tissue as possible, scarring is minimized. After the cancer is removed we may choose to: (1) let the wound heal by itself, (2) close the wound with stitches or (3) reconstruct the wound with a skin graft or flap. This decision is based on the safest method that will provide the best cosmetic result.


Will I have pain after the surgery?

Most patients do not complain of much pain after surgery. If there is any discomfort, Tylenol is usually adequate for relief. Avoid taking other pain medications as they may cause bleeding.


Preparing for Surgery

Medical History: Please complete the medical history form and bring it with you on the day of surgery.

Medications: Continue any medications (including aspirin) prescribed by your doctor. Aspirin however is a drug that may increase bleeding. If your doctor has not specifically told you to take it, we ask that you avoid aspirin for at least 10 days prior to surgery. Other pain medications which can increase bleeding include ibuprofen (Advil, Motrin, Nuprin) and naproxen (Alieve). Tylenol does not increase bleeding and may be taken any time before or after surgery.

If you are taking Coumadin, please notify our office before your scheduled surgery date as we may need to contact your doctor and/or obtain a blood test (Protime or INR) prior to the procedure.

Alcohol will also increase bleeding so please avoid alcoholic beverages for at least 24 hours before surgery

Cosmetics: Do not wear any cosmetics or perfume when scheduled for facial surgery.

Smoking: An association between cigarette smoking and delayed wound healing is well recognized. We ask that you minimize smoking as much as you are able, in the weeks prior to and following surgery.

Transportation: We suggest that you arrange to have a companion drive you to and from the clinic on the day of your surgery. Though it is not required that you bring someone else with you, you may also be more comfortable with someone to keep you company in the waiting room.

Eating: Eat a normal breakfast on the day of surgery.

Arrival: Please plan to arrive 15 minutes early so that we may complete your medical record and obtain necessary insurance information.

Parking: Free parking is available at the Baylis/SIU Clinics parking garage located on Miller Street between Rutledge and Bond Streets. We are located in the Dermatology Clinic on level 2 of the SIU Clinics Building (Room 2300).


Insurance Information

SIU Healthcare participates with most major health insurance plans offered in central and southern Illinois. We also accept assignment on Medicare and Illinois Department of Public Aid (IDPA).

Important: Please contact your insurance carrier before your surgery date to make sure all necessary authorizations and referrals have been obtained. Failure to comply with your insurer’s requirements may result in a delay in your surgery or a significant increase in your out-of-pocket payment responsibility.

You will be responsible for any deductibles or co-payments required by your insurer.

We will submit a claim to your insurance company for you. Please bring any necessary information (including the mailing address of your insurance company) with you to your visit.



If you have any questions, please call us at (217) 545-7890 or toll free at (800) 739-4711.





From the South: Take I-55 north to Business 55 (6th St.). Follow 6th St. north to Carpenter. Turn left on Carpenter. Turn right on Rutledge. Go north on Rutledge one block to Miller. Turn left on Miller.

From the West: Take Veterans Parkway north to Jones Pkwy. Turn right on Jones and proceed to the first stoplight (N.Grand Ave.). Turn left on N.Grand. Turn right at Rutledge (next stoplight). Follow Rutledge south to Miller. Turn right on Miller.

From the North or East: Take I-55 to Clear Lake Ave. (exit 98B). Proceed west on Clear Lake which turns into Jefferson. Turn right at 1st St. Turn left at Miller (5 blocks north, next street after Carpenter).