WHAT IS MOHS SURGERY?
Mohs surgery is a specialized, highly effective technique for removing skin cancers. It was developed in the 1930s by Dr. Frederick Mohs at the University of Wisconsin and is now practiced throughout the world. Mohs surgery differs from other skin cancer treatments in that it permits the immediate and complete microscopic examination of the removed cancer tissue so that all roots and extensions of the cancer can be eliminated. Mohs surgery has the highest reported cure rate of all treatments for skin cancer. Treating all skin cancers with Mohs surgery is not necessary. Mohs surgery is reserved for skin cancers that grow back after previous treatment, cancers that are at high risk of reoccurring, or cancers that are located in cosmetic areas where preservation of the maximum amount of normal skin is important.
WHY REMOVE SKIN CANCER WITH MOHS SURGERY?
Some skin cancers are deceptively large-far bigger under the skin than they appear to be from the surface. These cancers may have “roots” in the skin or involve blood vessels, nerves, or cartilage. Also, skin cancers that recur after previous treatments may send out extensions deep under the scar tissue that has formed. Mohs surgery is specifically designed to remove these cancers by tracking and removing these cancerous “roots”.
HOW IS MOHS SURGERY DONE?
There are three steps to Mohs surgery:
- The skin is completely numb using local anesthetic. The visible cancer is removed with a thin layer of additional tissue. This takes only a few minutes and the patient may return to the waiting room.
- The specimen is color coded to distinguish top from bottom and left from right. A technician freezes the tissue and removes very thin slices from the entire edge and undersurface. These slices are placed on microscope slides and stained for examination under a microscope. This is the most time consuming part of the procedure, often requiring an hour or more to complete.
- Dr. Bennion then carefully examines these slides under the microscope. This allows examination of the entire surgical margin of the removed tissue. That is, the entire undersurface and the the complete edge of the specimen is examined. All microscopic roots of the cancer can thus be precisely identified and pinpointed.
If more cancer is found on the microscopic slides or the margins, Dr Bennion uses the color coding to remove additional tissue only where cancer is present. This allows the Mohs surgery technique to leave the smallest possible surgical defect because no guess work is involved in deciding where to remove additional tissue. Only the tissue around the “roots” and extensions of the cancer is removed.
HOW LONG DOES IT TAKE?
Most cases can be completed in three or fewer stages, requiring less than three hours. However, no one can predict how extensive a cancer will be because the size of a skin cancer’s “roots” cannot be estimated in advance. We therefore ask that you reserve three to four hours in case additional surgical sessions are required.
WILL IT LEAVE A SCAR?
Yes. Any form of surgery leaves a scar. Mohs surgery, however, will leave one of the smallest possible surgical defects, and therefore a smaller final scar.
WILL I HAVE PAIN, BRUISING, OR SWELLING AFTER SURGERY?
Most patients do not complain of significant pain. If there is discomfort, Tylenol or Aleve is usually all that is necessary for relief. However, stronger pain medications will be prescribed when needed. You may have some bruising and swelling around the wound, especially if surgery is being done close to the eyes.
WILL MY INSURANCE COVER THE COST?
Typically insurance policies cover the cost of Mohs surgery and the surgical reconstruction of the wound. Please check with your insurance carrier for the exact information relating to your surgery.
HOW DO I PREPARE FOR SURGERY?
Get a good night’s rest and eat normally on the day of surgery. If you are taking prescription medications, continue to take them unless otherwise directed. However, avoid taking medications that contain aspirin for ten days before your surgery, unless the aspirin has been prescribed by your physician to treat a specific problem. Also please do not take any aspirin substitutes, such as Advil, Motrin, Nalfon, Naprosyn, etc. within 24 hours of surgery. You may, however, take Tylenol anytime before surgery. You may want to bring a book or magazine with you to occupy your time while waiting for your slides to be processed and examined. Also, Dr. Bennion recommends, but does not require, that you arrange for someone to drive you home after surgery is completed.