What is Mohs’ micrographic surgery?
Mohs’ micrographic surgery (called Mohs’ for short) is an operation for certain types of skin cancer. In Mohs’ surgery, the skin cancer is removed a layer at a time until all the cancer cells are gone.
The process involves:
- A doctor removes a thin layer of skin where the cancer is. The layer removed is processed, which can take about two hours, and this is then looked at under a microscope.
- If examination under the microscope shows that some cancer might still be present it is possible to determine precisely where it is. More tissue is then removed from only the area involved and examined.
- The process continues until there are no signs of any cancer cells left.
The surgery itself may only take a short time; however, the process of looking at the tissue can take several hours. Each procedure where tissue is removed and examined is referred to as a stage.
When is Mohs’ surgery used?
The majority of skin cancers will be removed in an operation without using this technique. Mohs’ surgery is particularly useful for:
- Skin cancers of the face and sensitive areas such as the eye where it is important to preserve as much normal tissue as possible.
- A cancer where it is difficult to see the extent with the naked eye.
- Cancers that have come back in the same place following previous treatment.
- Cancers which the doctor thinks have begun to spread into the surrounding area.
What are the alternatives?
Other treatments for skin cancer include:
- Surgery by ordinary removal.
- Radiotherapy - directing a beam of radiation at the cancer to destroy it.
- Chemotherapy (anti-cancer drugs) applied to the skin
- Cryotherapy - freezing the cancer to destroy it.
- Curettage and cautery – first the cancer is scraped away (curettage) and then the skin’s surface is sealed (cautery).
- Laser surgery (intense beams of light that cut away tissue).
- Photodynamic therapy – applying a special cream to the cancer under a dressing for four to six hours, which then destroys the cancer when a special light is shone onto it.
These treatment options will already have been considered in your case before deciding on Mohs’ surgery. Your doctor can talk to you about these options.
If the cancer is left it is likely to get bigger and may become more of a problem. Treatment is, therefore, usually advisable.
What are the benefits of this procedure?
Mohs’ surgery removes less healthy skin and tissue while making sure that the cancer has all been taken away. It has an extremely high cure rate (over 95%).
What are the risks of this procedure?
There are no complications specific to this procedure. Complications of any skin surgery include minor discomfort, wound infection, bleeding, a scar, numbness in the surrounding skin and nerve damage. If there is a high risk of any of these complications, this will be discussed with you before the surgery.
The vast majority of patients have this procedure without any problems.