Mohs surgery, also called Mohs micrographic surgery, is a procedure used in the treatment of skin cancer. The cancers afflicting the eye area are basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). These cancers are located on the eyelids or around the eye area. Since the procedure involves the removal of only tissue with cancerous cells, surgeons commonly use it in specific areas of the body to minimize the removal of healthy tissue.

Basal cell cancers grow in the deepest layer of the skin. Exposure to sunlight causes this type of cancer. While basal cell cancer is the most prevalent type of skin cancer, squamous cell cancer comes in second. Both grow just below the outer layer of the skin. Detecting and treating both basal cell and squamous cell cancers present a good prognosis.


Mohs surgery, if successful, eliminates cancer cells from the body. It is ideal when BCC and SCC turn aggressive, become large or appear in areas with little tissue like the eyelid, nose, ear and so on. It is also necessary in recurring cases of skin cancer.

Mohs surgery is also used in the treatment of rare skin cancers like Merkel cell carcinoma, Dermatofibrosarcoma protuberans (DFSP) and Extramammary Paget's disease. It can also treat an aggressive type of skin cancer called melanoma. Melanoma resides inside the eye as opposed to the eyelid. However, Mohs surgery can only treat melanoma in its early stages

Preparation & expectation before Surgery

Only a surgeon trained for this type of surgery will attend to a patient due for Mohs surgery. Mohs surgeons are trained dermatologists.
The surgeon will perform this surgery in the office or surgical suite in most cases.  Patients are admitted to hospital only if extensive surgery is required.
Before the surgery, the surgeon gives the patient a set of instructions to follow. They may include: 

  • To stop smoking
  • To avoid eating certain types of foods or beverages some hours before the procedure
  • Taking a full day off to allow room for the procedure and the resultant healing process
  • Putting on hold certain medications they may be using such as over-the-counter painkillers, supplements and others


On the day of the surgery, the surgeon will examine the affected area. Medical professionals will prep the patient for surgery by having the skin around the cancerous area numbed to protect against pain. The surgeon will administer medicine that aids in relaxation as the patient stays awake during the procedure.
The surgeon starts by cutting out skin cancer. He/she will proceed to remove any thin layer of surrounding tissue suspected of containing cancerous cells. The surgeon examines this tissue under a microscope in a lab within the facility. Should cancerous cells be spotted, the surgeon will remove another adjacent layer and repeat this process until cancer cells can no longer be detected under the microscope. Most tumors require 1-3 stages for total removal. The procedure often takes a few hours. The patient is then bandaged and can wait comfortably.

The surgeon will decide whether to treat the wound. Some wounds will heal on their own while others will require stitches. The surgeon may choose to do a skin flap by shifting skin from an adjacent area to cover the wound. Where a wound is large, the surgeon will refer the patient to another specialist for treatment.

After care, recovery, results

Of all the skin cancers, Mohs surgery has the highest cure rate.

One advantage of Mohs surgery is that it reduces the need to remove healthy tissue since the surgeon checks every tissue removed. Consequently, the operation allows for complete removal of the cancerous cells as the patient gets to keep as much skin as possible. It is a unique benefit, unlike other skin cancers, because the surgeon has a clear vision of where the cancer ends. This way, the wound heals better and quickly with minimum cosmetic damage. 
Sometimes the patient may need reconstructive surgery depending on the location and size of the cancerous cells. If the reconstruction involves the eye, eyelid and face, a specially trained ophthalmologist may be called in to assist with the procedure.

The surgeon will closely monitor the patient to ensure that healing is taking place as it should. The patient may receive the following information:

  • Appointments
  • What medication to take
  • When to change bandages
  • How to clean the surgical site
  • When to return to activities like wearing makeup and exercising

Risks & complications

Complications for Mohs surgery may include:

  • Bleeding
  • Infection
  • A keloid (enlarged scar)
  • Itching in the affected area
  • Pain or tenderness in the surgical area