Hi everyone. Because so many Mohs surgery procedures are performed each year, I want to talk a little bit about Mohs surgery so you should know what to expect from the experience and how it can alter your appearance. Mohs micrographic surgery is named after Dr. Frederick Mohs who pioneered this process in which the surgical margins are checked during the procedure to ensure complete removal of the skin cancer before you leave the surgeon’s office.
There are two major advantages to this treatment plan. First, and most importantly, the entire cancer is removed with pathologic confirmation. Secondly, the scars are smaller because less normal skin is removed because the skin cancer is cut out in layers. This is important as a scar from a non-Mohs skin cancer excision usually ranges from one to two inches. On a person’s back, an inch scar is not so bad but an inch long scar on the nose is much more noticeable As a result, this procedure is indicated for certain skin cancers on the face or other areas for specific types or abnormally large or recurrent tumors.
Once the skin cancer is completely removed during the Mohs procedure, you then have a “hole” or “defect” from the excision that is then closed, usually with stitches. In most cases, the Mohs surgeon will stitch this area closed, although a plastic surgeon or otolaryngologist (“ear, nose, and throat doctor”) may be involved depending on the procedure necessary to close the hole.
There are usually four main methods of closing the defect. Simply closing this area with stitches is commonly performed as there is often enough mobility of the surrounding skin to allow for this. If not, a skin graft may be taken in which skin is cut from another area and “transplanted” to cover the defect. For example, taking a piece of skin from near the ear to graft onto the nose. The third option is a skin “flap”, in which skin is moved and shifted to allow for stitches to pull the skin together. For example, moving skin from the forehead or cheek onto the nose. The fourth option is just to allow the skin to heal in on its own and this is termed "healing by secondary intention." This is a good choice for certain areas, although it usually requires more care as it takes several weeks to months for the skin to heal itself. In this case, the scar usually takes the shape of the original hole.
Procedures such as grafts and flaps can sound scary but there is no reason to fear them. The scars are often hidden in the regular folds and wrinkles that we all have on our faces! Usually, stitches on the face are removed about one week after the procedure and then the scar continues to heal and over time, the scar will become less noticeable. Surgeries performed near the eyes often result in bruising causing the appearance of “black eyes” for several days after surgery.
Silicone pads may help prevent hypertrophic (thick) scars although there is still no way to guarantee a perfect scar. Vitamin E containing creams and other creams designed to aid scarring may help but none have definitively been proven to aid the final outcome. If the scar is thicker than expected, you can talk with your surgeon about “dermabrasion” in which the skin is effectively “sanded down” to smoothen it and make the scar thinner. Scar revisions can also be performed in which the scar is excised or re-oriented to improve the final outcome.
Fortunately, most procedures heal without problems and these postoperative modifications are not done often. Always discuss your individual concerns with your surgeon so that any questions you have are addressed. But remember, it is hard to predict how deep the skin cancer has spread until the Mohs procedure is done so it is often impossible to predict how the scar will ultimately appear until the surgery is done. I hope this helps take some of the fear and uncertainty out of the Mohs procedure for you.