The Mohs Micrographic Surgery Technique

Over 50 years ago, Dr. Frederic Mohs developed a technique (known then as chemosurgery) for the microscopically controlled removal of skin cancers. Mohs Surgery is done under local anesthesia and rarely requires hospitalization. Mohs Micrographic Surgery requires highly specialized training and personnel, and is usually available only in larger cities. It is a time-consuming technique, but has a very high cure rate (99% of first-time skin cancers and 95%-97% of skin cancers that have come back). The cancer types that we treat with Mohs Surgery are basal cell carcinoma, squamous cell carcinoma and other skin cancers.

Learn more about Mohs Surgery, including what the Mohs procedure is, see the Mohs step-by-step process, and get answers to the most-asked questions about the procedure, by visiting the American College of Mohs Surgery patient education website.


The patient, who may be given a sedative upon request, is numbed with local anesthesia. (Note: if a sedative is given you must have someone drive you home!) The numbing, which burns a little, is all the pain that you will feel. The surface of the cancer is shaved off to confirm the diagnosis in our laboratory. The visible cancer is then scraped to determine where the roots go. Then a thin layer of skin is cut out. The tissue is processed in our laboratory, which takes 45 minutes to an hour. The tissue is then carefully and completely viewed by Dr. Coldiron under the microscope to make sure all cancer is out. If all the cancer is not out, a map of your cancer is marked and a second thin piece corresponding to the map is cut out and the process repeated. This way no more tissue than is absolutely necessary is taken out. Most cancers are completely removed in two or three trips to the operating room, but very large, longstanding or aggressive cancers may take longer. Plan on being in the office all day. Bring a friend and a book. In rare instances, the patient may have to come back the next day to have the process completed.
Mohs Surgery cuts out the bare minimum of normal skin needed for a high cure rate (95%-99%). This is important in critical areas. Once a tumor has come back, conventional treatment (cutting out, scraping and burning, radiation) offers only a 50% cure rate. Mohs Surgery is worth the time it takes in order to get all the cancer out and to get the smallest possible hole.
Skin cancers that we treat with Mohs Surgery usually do not spread to other parts of the body and cause death. They can, and often do, destroy the skin and structures where they grow and locally spread. A skin cancer left untreated long enough can cause death if it invades a vital structure. These skin cancers do not go away on their own! Though they may seem to heal over, if untreated, they always come back bigger, and with deeper roots. While the removal of skin cancer is not an emergency, in general they should be removed within a month or two of diagnosis.
Try to get a good night’s sleep, eat breakfast, and get to the office on time. Wear comfortable clothing that you can easily get in and out of. Please leave the whole day open for Mohs Surgery. While we often get all the cancer out by noon, the wound may be repaired in the afternoon. Take your usual medicine unless we tell you otherwise.
A local anesthetic, usually Xylocaine, is injected around the skin cancer to numb the area. This burns only a little, and the numbness lasts several hours after the injection. More Xylocaine may be injected later so that there is no pain if more surgery is required. Pain after going home is unusual, and two regular Tylenol by mouth every four hours is usually adequate for any pain.
No, probably not. Only rarely do Mohs Surgery patients need to be hospitalized. Whenever possible, Mohs Surgery is done on an outpatient basis. We can, however, hospitalize patients if they need it.
We photograph most patients before and after their surgery. These photos are used by us if the insurance company questions us regarding your claim, and they may also be used for teaching. We also send a picture to your referring physician.
We recommend discontinuing certain medications two weeks prior to surgery (see table below). Discuss this with the doctor who prescribed them prior to discontinuing them to make sure it is safe. Aspirin interferes with your blood’s ability to clot. If you need pain medicine take Tylenol or acetaminophen. Do not drink alcoholic beverages for three days before or after surgery. Alcohol causes the skin to flush and interferes with the clotting of the blood.
Advil Echinacea Nuprin
Aggrenox Ecotrin Orudis
Aleve Effient PAC Analgesic
Alka Seltzer Empirin Products PeptoBismol
Anacin Emprazil
Anaprox Equagesic Products Percodan
ASA Excedrin Persistin Products
Ascoden Feldane Phenaphen
Ascriptin Fish Oil Plavix
Aspergum Florinal Products Pradaxa
4 Way Cold Tablets Prasugrel
Aspirin Garlic Rivaroxaban
BC Powder Ginger Robaisal
Brilinta Gingko Biloba Robixisal Products
Bufferin Ginseng Rutin
Cephalgesic Guaifenesin Salflex
Cheracol Halfprin Sine Aid
Children’s Aspirin Haltran Sine Off
Clinoril Ibuprofen Products (Advil, Motrin, Nuprin, Ibuprophin) St. John’s Wort
Congesperin Indocin St. Joseph’s Aspirin for children
Contact Indomethacin Ticagrelor
Cope Meclomen Tolectin
Coricidin Medipren Trigesic
Coumadin Melatonin Trilisate
Cramp End Midol Ursinus
Dabigatran etexilate Midol IB Vanquish
Darvon Products Momentum Vitamin E
Dipyridamole Motrin Voltaren
Disalcid Nalton Warfarin
Doans P.M. Naprosyn Xarelto
Dolobid Norgesic Products Zorprin Products
Dristan NSAIDS (nonsteroidal anti-inflammatories)
When it is determined that your cancer has been completely removed, there will be a hole left where it was. A decision will then be made on the best way to manage this wound. If it is small, it may be allowed to heal on its own. It may also be sewn shut, or be repaired with a skin graft or flap. Some wounds are best handled by a plastic or reconstructive surgeon. The method used depends on many variables. In many cases, the repair may be arranged to be done by a specialist before the Mohs Surgery. You will be given a detailed instruction sheet on how to care for your wound at the conclusion of your surgery.
Yes. Any treatment of skin cancer will leave a scar. Mohs Surgery preserves as much normal skin as possible resulting in a scar as small as possible.
Yes, we suggest you do bring someone with you to drive you home and keep you company during the procedure. If this cannot be arranged, public transportation or a taxi may be adequate. Do not count on driving yourself. If you receive a sedative, or have a skin cancer near your eye, you will not be able to drive.
Although uncommon, about one in 200 patients may experience some bleeding after going home. If this occurs, lie down and apply steady firm pressure over the wound as close as possible to the area that is bleeding. Apply this pressure continuously for 15 minutes (time it). While applying pressure, do not lift the bandage to check for bleeding. If the bleeding persists after 15 minutes of steady pressure, call the office at (513) 221-2828 for instructions. You can also reach Dr. Coldiron at home (859) 291-1339 or his mobile phone (513) 550-2828, or go to the nearest emergency room. If the bleeding stops after 15 minutes, as it almost always does, you may apply an additional layer to the dressing if it is soiled. Do not remove the original dressing until the following day when you clean the wound.
All wounds develop a small ring of redness that will gradually disappear. Severe itching with extensive redness usually indicates an allergy to the ointment used to dress the wound or a reaction to the adhesive tape. You should call the office if this happens. Swelling is common after Mohs Surgery, especially around the eyes. This is a normal response. You may develop bruises around the area of surgery. Initially all wounds drain a clear or pink tinged fluid, which is normal. Infection is unusual. If the wound has been left to heal on its own, as is sometimes done, a thick yellowish discharge will develop by the second week. This is not pus but rather dead tissue separating from the base of the wound. As this separates, there may be a slight amount of bleeding.
You may feel a sensation of tightness (or drawing) as the wound heals, but this is normal and will lessen as time goes on. Frequently, skin cancers involve the nerves of the skin, making it necessary to cut the nerves. It may take a year or more after surgery before the feeling returns to normal. Sometimes the area stays numb permanently. Much less commonly, one of several nerves that control the muscles of the face are involved with the cancer. Every attempt is made not to damage these nerves, but sometimes they must be cut out to get the cancer out. This may result in temporary or permanent paralysis of certain muscles of the face. If permanent paralysis occurs, there are restorative surgical procedures that can be performed. The new skin that grows over a wound contains many more blood vessels than the skin that was removed. This results in a red scar, and the area may be sensitive to temperature changes (such as cold air). This sensitivity improves with time, and the redness gradually fades. If you are having a lot of discomfort, try to avoid extremes of temperature. The new skin lacks the ability to protect itself from the sun so it will blister readily. You must protect it with sunscreen (factor 15 or higher) at all times. Patients frequently experience itching after their wounds have healed because the new skin that covers the wound does not contain as many oil glands as previously existed. Applying a small amount of plain Vaseline will help relieve this itching.
We usually like to see you two months after stitches come out. A period of observation of at least five years is essential. This follow up can be done with your dermatologist. There are several reasons why this is important. Should there be a recurrence of the skin cancer after Mohs Surgery, it may be detected at once and treated. Experience has shown that if there is a recurrence it will usually be within the first year following surgery. Studies have shown that once you develop a skin cancer there is a high risk that you will develop others in the years to come. You should watch for an open sore that does not heal and bleeds easily. If you notice any suspicious areas, it is best to check with your referring physician to see if a biopsy is indicated.
No, not entirely. Sunshine cannot harm you as long as you are protected with a factor 15 or greater sunscreen, avoid burning, and use discretion. You should not restrict your activities to the degree that it would interfere with your lifestyle. Sunlight is probably the main cause of skin cancer, and patients who have developed one skin cancer will often develop another one at a later time. It is recommended that you apply a factor 15 or higher number sunscreen to all exposed areas. It is important that men and women remember to include the tops of their ears, and men cover their bald spots. It is best to apply the sunscreen 15 minutes before going outdoors. Reapply it liberally, especially after swimming or exercise. In addition to sunscreen, a broad brimmed hat and long sleeve cotton shirt provide good sun protection. Factor 15 sunscreen blocks 97% of the harmful rays, while higher numbers (20, 25 even 50), block up to 99% of the harmful rays. You can buy any brand that is factor 15 or greater. There have been exaggerated reports of sunscreens being carcinogenic. These reports are based on sunscreen breakdown products in bacterial tests. The risk of cancer is much, much greater if you do not wear a sunscreen, so we strongly recommend that you do.
Share our site with friends and family   Facebooktwittergoogle_plusmail