Mohs surgery

Overview

Mohs surgery, or Mohs micrographic surgery, is a precise method for removing high-risk skin cancer. The procedure involves excising the tumor in layers, starting with the visible part along with a margin of surrounding skin. Each layer is examined under a microscope, and if cancer cells are detected at the edges, additional tissue from those areas is removed and examined. This process continues until no cancerous cells are found.

One of the main advantages of Mohs surgery is its ability to target only cancerous tissue while preserving healthy skin. This makes it especially effective for treating skin cancers on delicate areas such as the face, scalp, ears, hands, feet, and genital regions.

Typically performed in a doctor’s office or outpatient surgical center, Mohs surgery requires patients to wait while each tissue layer is examined. If cancer is detected at the margins, more tissue will be removed. This can be a lengthy process, so it’s a good idea to bring something to pass the time, like a book or electronic device.

During the surgery, the surgeon meticulously removes the tumor and examines each layer of cells under a microscope, ensuring that all cancerous tissue is eliminated. This step-by-step approach allows for the gradual removal of cancer while preserving as much healthy tissue as possible.

Reasons for undergoing the procedure

Mohs surgery is primarily used to treat the most common types of skin cancer: Basal Cell Carcinoma (BCC) and Squamous Cell Carcinoma (SCC). It can also be employed for other skin cancers, including certain melanomas, dermatofibrosarcoma protuberans, microcystic adnexal carcinoma, sebaceous carcinoma, and extramammary Paget disease, among others.

Risks

The Mohs procedure itself carries relatively little risk. Please talk to your surgeon about any concerns you may have regarding the Mohs procedure as well as your specific health issues. The following are the typical risks connected to Mohs surgery:

• Infection.
• Excessive bleeding.
• Poor wound healing.
• An unforeseen large wound.
• Scar formation.
• Temporary or permanent loss of nerve function (muscle or feeling).
• Tumor regrowth following removal (particularly common in large, long-standing cancers and previously treated tumors).

Before the procedure

Before undergoing Mohs surgery for skin cancer, your dermatologist will perform a physical examination of the spot and surrounding tissue. During this appointment, you and your dermatologist will review:

• The results of your biopsy.
• Your skin cancer diagnosis, the available treatment options, and the benefits and risks of Mohs surgery.
• Your medical history and a list of all medications and supplements you are currently taking.

The use of preoperative antibiotics will depend on the location of the surgical site and your overall health.

During the procedure

Skin containing cancer cells is removed layer by layer during the Mohs procedure. The standard steps in the process are as follows:

• Your surgeon removes any visible, elevated portion of the tumor and a thin layer of tissue from the site after injecting an anesthetic to numb the skin surrounding the cancer cells. Your surgeon will work to keep as much healthy, normal skin as possible.
• They label the tissue in order to make a map of the location and identify the top, bottom, right, and left.
• They freeze, cut, and dye the tissue in the doctor’s office right away. Although it varies from case to instance, this process takes around an hour.
• Under a microscope, your surgeon looks at the entire bottom and outside edges of the excised tissue layer.
• Should there be any cancer cells in the sample, your surgeon uses the marks and map to pinpoint their exact location. Then, he or she removes a tiny layer of tissue from the area where the cancer cells are still present.
• Additional tissue layers are removed and analyzed microscopically until no more cancer cells are detected.

Your surgeon will go over the best course of action for wound management once the skin cancer has been completely removed. The options consist of:

• Allowing your injury to mend naturally (second intention healing).
• Using stitches to close your wound.
• Closing your incision with a graft, which uses tissue from another part of your body, or a skin flap, which uses tissue from the surrounding skin.
• A mix of the previously mentioned strategies.
• Using a different surgical specialist, such as a facial plastic surgeon (often saved for a tumor larger than expected) or oculoplastic (around the eye).

To be sure, during a Mohs operation most people are awake. Your surgeon will inject anesthetics, or numbing agents, into the affected area. While doctors examine your tissue, you won’t experience any discomfort or pressure, and you can relax in the operating room or waiting area. You might still be numb after the first injections if you need additional skin removed, or you might require more injections.

Mohs surgery can be completed in a few hours or all day. The tumor itself determines how long the process takes; larger, deeper tumors require more time to fully eradicate.

After the procedure

After Mohs surgery, most patients experience mild to moderate pain, which gradually subsides over a few days and is usually manageable with acetaminophen. Individuals who undergo the procedure on their scalp or have wounds larger than three square centimeters often report more pain compared to those with surgery on other areas.

Outcome

After Mohs surgery, scars typically take 12 to 18 months to fully heal. During this time, the scar will gradually develop and fade, so patience is required. If you’re dissatisfied with the appearance of your scar, discuss your options for scar revision with your surgeon.