Mohs Micrographic Surgery Program

The Micrographic Surgery program - also known as the Mohs micrographic surgery - is an outpatient program used to treat some forms and cases of skin cancer.

What is micrographic surgery? How it is different from other skin cancer treatments?

Micrographic surgery, which is also known as Mohs after Frederick Mohs, the doctor who developed the treatment, is used to treat certain kinds of skin cancers on some areas of the body.

Skin cancers can be like iceburgs; what you see at the surface is just a small part of a larger structure. Mohs is a minimally-invasive surgery that allows health care providers to directly target cancerous tissues at and below the surface of the skin, saving as much healthy tissue as possible.

Mohs can be most beneficial for treating patients who have cancers that:

• could have a high likelihood of recurring or that have recurred following other treatments
• are diagnosed in areas where preserving as much healthy tissue as possible is important, such as skin cancers on the head and neck, including the nose, ears, eyelids, lips and scalp.
• have edges (borders) that are hard to distinguish from healthy tissue
• are large or aggressive/advanced.

Traditional treatments for certain types of skin cancers can have two limitations, both of which may result in added treatments, added costs, travel and stress for patients, and can affect their outcomes.

In some cases traditional treatments can result in too much healthy tissue being removed, along with the tumor, resulting in the need for significant reconstructive surgeries, physical deformities or restrictions. 

In other cases, too little tissue may be removed, meaning that harmful cancer cells may remain, along with the need for additional procedures to prevent their cancer from returning or advancing.

Mohs increases the chance of a cure and reduces the need for additional treatments or surgery. It also prevents patients from having to wait for tissue samples to be sent for testing and them waiting, often weeks, for confirmation that no evidence of cancer remains. This means they can have their cancer removed and reconstruction of their wound all in the same day.

How do I access this treatment/surgery?

Nova Scotia Health offers micrographic surgery to treat some skin cancers involving the head and neck, including basal cell and squamous cell carcinomas, which are two of the most common skin cancers. It is also used for some more rare forms of skin cancer known as adnexal carcinomas.

Nova Scotia Health offers this service through a partnership with a dermatologist specializing in micrographic surgery. 

Skin cancer patients who meet the criteria for the program may be referred by their specialist or primary health care provider.

To be eligible, patients must have a skin biopsy (removal and testing of small sample of tumour) to confirm if they have skin cancer and the type of cancer they have. They must also meet at least one other criteria outlined on the referral form (PDF)

• must have skin cancer that could have a high likelihood of recurring or that has recurred following other treatments
• skin cancer is diagnosed in an area where preserving as much healthy tissue as possible is important, such as on the ears, nose, lips or eyelid.
• edges (borders) of skin cancer are hard to distinguish from healthy tissue
• skin cancer is large or aggressive/advanced.

Once the referral is received it will be reviewed to confirm eligibility and an initial appointment will be scheduled to discuss how the surgery works.

Skin cancer patients may be referred for the surgery by their specialist or primary health care provider if they meet the Mohs criteria.

Mohs can be most beneficial for treating patients who have cancers that:

• could have a high likelihood of recurring or that have recurred following other treatments
• are diagnosed in areas where preserving as much healthy tissue as possible is important
• have edges (borders) that are hard to distinguish from healthy tissue
• are large or aggressive/advanced.

How does micrographic surgery work?

During Mohs surgery, a specially-trained team, including a dermatologist and nurse, work to gradually remove small portions of tissue.

These small samples are stained with dyes (to make cells more visible and easy to distinguish) and orientated.

Next they are taken to a laboratory at the clinic where a medical laboratory technologist prepares the samples to be examined by the surgeon under a microscope.

These steps are repeated until there is no evidence of cancerous cells in the outside edges of the samples.

Once your tumour is removed and the team feels confident that only healthy tissue remains, the surgeon will reconstruct the areas where your tumour was removed.

In some cases healthy tissue may be removed from other parts of your body to cover the area where the tumour is removed. Other times the wound can be closed by pulling together and stitching tissues surrounding the wound. 

Your surgeon will discuss your unique situation and your preferences, to help ensure you know what to expect and to that you are as comfortable as possible with the outcome.

What should I expect the day of my procedure?

We advise patients to expect to be at the clinic for most of the day for your surgery as well as reconstruction of the area where the tumour is removed.

Because all patients require is localized freezing -- an injection to numb the tumour and surrounding tissues -- you will be awake and able to talk to your health care team during your procedure.

While your samples are being tested you will be able to sit comfortably in a waiting area. We recommend you bring along a book, newspaper or tablet to help pass the time.

How long your whole procedure takes will depend on the size and complexity of your cancer, how many layers of skin and tissue need to be removed and tested and how long it takes to reconstruct the area where the tumour was removed.

Patients can eat and drink the day of their Mohs procedure and are encouraged to bring snacks/lunch and something to drink.

What happens after my procedure?

You will be given instructions on how to care for your wound after surgery and where to call if you have questions or concerns.

Most patients are able immediately resume normal activities following their procedure. Your health care team can discuss any special precautions you may need to take.

Most patients will be given an appointment to return for a follow-up exam within a few weeks of their procedure.

Some patients with larger or more complicated cancers may also be scheduled for an appointment three-months following their procedure to assess their progress.

Information for referring primary health care providers and specialists

Nova Scotia Health offers micrographic surgery to treat some skin cancers involving the head and neck, including basal cell and squamous cell carcinomas, which are two of the most common skin cancers. It is also used for some more rare forms of skin cancer known as adnexal carcinomas.

To be eligible, patients must have a skin biopsy (removal and testing of small sample of tumour) to confirm if they have skin cancer and the type of cancer they have. They must also meet at least one other criteria outlined on the referral form (PDF).