What You Need to Know About Mohs Surgery

Medically reviewed by Sarah Taylor, MD on June 5, 2017Written by Corey Whelan on June 5, 2017

What is Mohs surgery?

Mohs micrographic surgery is a highly effective treatment for the removal of certain types of skin cancer lesions. It was developed by a medical student named Frederick Mohs who went on to become a general surgeon in the 1930s. The procedure was modified during the 1970s by Dr. Perry Robins, a dermatologist and founder of the Skin Cancer Foundation.

Mohs surgery is still the most successful and least invasive technique for removing skin cancers, such as basal cell carcinoma and squamous cell carcinoma. It’s also used successfully in some melanoma cases. Melanoma is the deadliest form of skin cancer.

What is the purpose of Mohs surgery?

Mohs surgery is a painstaking procedure. It requires microscopic analysis of tissue cells while the surgery is taking place. The borders of each thin layer of tissue are analyzed for potential malignancy as they are removed horizontally. This technique is designed to remove the entire tumor with minimal amounts of healthy tissue. This results in less disfigurement. For this reason, Mohs surgery is ideal for removing skin cancers from the face, ears, or genitals.

The procedure is highly effective for skin cancers that have high rates of recurrence. It’s also effective on aggressive or large lesions. Mohs surgery is also used when lesions have ill-defined borders.

What are the risks of Mohs surgery?

Mohs surgery is performed with local anesthesia. This removes the common surgical risks that come with using general anesthesia.

Risks that are associated with Mohs surgery include temporary bleeding, pain, and tenderness around the area being removed. More serious problems can occur, but they are rare. These include keloid (raised) scarring and permanent or temporary numbness or weakness in and around the affected area.

Mohs surgery requires extensive training and skill. The surgeon needs to accurately map out the tumor and analyze each layer of tissue removed during surgery. Working with a highly experienced dermatologist is important. They should be fellowship-trained and certified by the American College of Mohs Surgery. Trained physicians are not only experts in reading slides, but also in closing the wound as beautifully as possible. When choosing a surgeon, ask them about their level of training, if they are fellowship-trained, and the number of procedures like yours that they have personally performed.

How do you prepare for Mohs surgery?

As with any surgery, discuss your allergies, medications, and supplements with your doctor. If you drink one or more alcoholic beverages daily, ask if you should stop your intake prior to surgery. Also let your doctor know if you smoke cigarettes or use any other tobacco or nicotine product.

Come clothed for the procedure in comfortable, loose-fitting clothing.

If you’re having the surgery done near your eye and wear contact lenses, ask your doctor if you should remove them for the day. If you wear dentures and need surgery near your mouth, you may need to remove your dentures during the procedure.

You’ll be awake for the entire surgery. It’s hard to predict how long Mohs surgery will last. Three or four hours or longer is common. The procedure may comprise several waiting periods while the layers of removed tissue are analyzed. You’ll be able to sit up and relax during these wait times. You may wish to bring something to occupy yourself, such as a book, crossword puzzles, or knitting.

Even though the time frame for Mohs surgery is hard to predict, make plans ahead of time to have someone waiting who can take you home once the surgery ends. Don’t schedule anything else for the day other than rest.

Since you will not be under general anesthesia, it’s usually recommended that you eat breakfast before arriving.

How is Mohs surgery performed?

Mohs surgery is always performed in a medical facility that houses a laboratory.

An anesthetic will be injected into the area where the tumor is located, numbing it completely and making the procedure painless. Your surgeon will use a scalpel to gently remove the tumor, along with one layer of tissue from around it. The tumor and tissue will be taken to the lab for analysis while you wait. This waiting period may last up to an hour or longer, but you’ll be able to use the restroom if you need to. If the tumor is not next to your mouth, you’ll also be able to have a light snack or something to drink.

In the lab, the tissue sample will be sectioned and analyzed. If cancer is found, an additional layer of tissue will be removed in the exact area where the malignancy was located. This process continues until no more cancer cells are detected.

If you have malignant melanoma, it’s vitally important that your surgeon remove every single microscopic melanoma cell. This reduces the chance of cancer spreading (metastasizing) to other parts of your body. New technologies, including stains that highlight malignant cells under a microscope and other immunohistochemistry techniques, help to further diminish this risk.

If the procedure is very long, you may require an additional injection of anesthesia.

Afterward, your surgeon will determine the best way to repair the area. If the surgical wound is very small, it may be left to heal naturally, or it may be closed with stitches. Sometimes your surgeon may use skin grafting or the construction of a skin flap. If the tissue removal was extensive, you may require additional plastic surgery at a later time.

What is the recovery period from Mohs surgery like?

After the surgery ends, you’ll be tired. For the next several days take it easy and avoid any strenuous activities, including bending.

After surgery, you may be prescribed antibiotics to help prevent infection.

The surgical site will be covered with a bandage before you leave. You should leave this bandage on for 24 to 48 hours. Your doctor will instruct you on when to remove the bandage and on the type of wound care you should use. Using ice packs is a common recommendation.

Ask your doctor what type of medication you should take if you experience postsurgical discomfort. Minor discomfort and light bleeding are to be expected. If you experience heavy bleeding, or any other reaction that concerns you, let your doctor know immediately.

CMS Id: 122667