What is Mohs?

Mohs surgery is an effective, precise, tissue-sparing technique for the total removal of skin cancers. It is named for Frederic Mohs, MD, who pioneered this form of cancer treatment over 60 years ago. MOHS, as an acronym, stands for Microscopically Oriented Histographic Surgery.

Mohs Procedure

The surgical site will be identified by the doctor and verified by the patient.

A local anesthetic will be used to numb the area.

A sample of tissue will be taken by the doctor.

The sample of tissue will be taken to the lab where it will be processed and made into a slide to be viewed under the microscope.

While the tissue is being processed, the patient will wait in the waiting room with a bandage on their wound.

If positive skin cancer cells are identified under the microscope, they will be marked on a map and the patient will be called into the room for another sample to be taken. This process will be repeated until the margins are clear and there are no positive skin cancer cells remaining.

After clear margins are obtained, reconstructive options will be discussed.

The Key steps in Mohs procedure:

Source: www.mohscollege.org

Step 1

The roots of a skin cancer may extend beyond the visible portion of the tumor. If these roots are not removed, the cancer will recur.

Step 2

The visible tumor is surgically removed.

Step 3

A layer of skin is removed and divided into sections. The Mohs surgeon then color codes each of these sections with dyes and makes reference marks on the skin to show the source of these sections. A map of the surgical site is then drawn.

Step 4

The undersurface and edges of each section are microscopically examined for evidence of remaining cancer.

Step 5

If cancer cells are found under the microscope, the Mohs surgeon marks their location onto the "map" and returns to the patient to remove another layer of skin - but only from precisely where the cancer cells remain.

Step 6

The removal process stops when there is no longer any evidence of cancer remaining in the surgical site. Because Mohs surgery removes only tissue containing cancer, it ensures that the maximum amount of healthy tissue is kept intact.

What are the Advantages of Mohs Surgery?

There are many advantages to having Mohs. Mohs is a one day outpatient surgery and is the most effective treatment of skin cancer. Immediate tissue processing and examination occurs so there is no need to wait a week or more for pathology results.

The Mohs surgeon can pinpoint with the microscope the areas where there is cancer and selectively remove tissue only from those areas. In this way, the skin cancer is traced out to its roots with little guesswork involved, which results in (1) the removal of as little normal tissue as possible, and (2) the highest chance of curing the patient. Other forms of therapy frequently have only a 50-75% chance of success in curing skin cancers that have had previous treatments that failed.

How long does it take?

Total removal of a skin cancer, which may involve several surgical sessions, is usually completed in one day. After the surgery, a decision is made as to the best way to manage wounds created by the surgery. This will be discussed later.

How effective is MOHS surgery in the treatment of skin cancer?

Using the MOHS technique, the percentage of success is very high, often 95-99%, even if other forms of treatment have failed. Therefore, with this technique, an excellent chance of cure is achieved. However, no one can guarantee a 100% chance of cure.

Will the surgery leave a scar?

Yes. Any form of surgery will leave a scar. However, the MOHS procedure tends to minimize this as much as possible.

Will my insurance cover MOHS surgery?

Most health insurance policies cover the total cost of Mohs surgery and the reconstruction of the resultant surgical area. Every individual policy is different. Please contact your insurance company directly to discuss your individual payment benefits. If you have any additional questions regarding costs please contact our billing department.

Should someone come with me on the day of surgery? Do I need someone to drive me home?

Yes. It is recommended that you have someone drive you home – and it may be pleasant to have company while sitting in the waiting room.

How long does the surgery take?

Each step (or stage) of the surgical procedure takes an average of 2 to 3 hours. The initial surgical procedure is approximately 30 minutes; the time may be longer in extensive cases. However, after the tissue removal it takes approximately 2 hours for the slides to be prepared for the physician to complete and complex microscopic examination. Several surgical stages and microscopic examinations may be required. If you have more than one surgical area, the time involved will be more extensive.

Does it hurt?

A local anesthetic, usually Lidocaine is injected around the skin cancer to numb the area. A burning sensation is felt during the injection of the anesthetic. The surgery does cause slight discomfort.

How many surgical sessions are there?

The average number of surgical sessions is two or three, so most patients are finished by mid-day. In case you must stay longer, bring a light lunch with you. Please- no alcoholic beverages. Alcohol dilates blood vessels and may promote bleeding.

Will I have pain after the surgery?

Most patients do not complain of pain. However, pain is an individual phenomenon and if you’re uncomfortable we recommend taking 2 tablets of Extra Strength Tylenol every 4 hours. Avoid aspirin-containing compounds (such as Anacin, Bufferin or Ibuprofen) as these may produce bleeding. We also recommend stopping Vitamin E and garlic supplements.

You may experience some bruising and swelling around the wound, especially if the surgery is performed near the eye area.

What’s the next step after MOHS surgery has been completed?

When we have determined that the skin cancer has been completely removed, a decision is made about the wound created by the surgery:

1. The wound may be allowed to heal by itself.

2. For small post-surgical sites, direct closure by suturing the sides of the wound together may be possible.

3. In certain areas of the body, there is very little tissue that can be stretched for coverage of a wound. In this care either a skin graft or a skin flap must be used. You will have stitches anywhere from 5 to 14 days depending upon the surgical site.

You will need to return to the office within the time frame recommended for suture removal. With any of the above options, your surgical site will most likely require daily care at home; you will be given detailed instructions following your surgery.

David R. Byrd, M.D., will recommend which of these options will be best for your individual case.

How long will the wound take to heal?

If the wound is allowed to heal by itself (a process called “granulating in”), it usually heals in four to eight weeks. When healing is well advanced, you will be permitted to stop the daily dressing changes.

My skin cancer has been treated several times. Will I ever be cured?

A frequent reason why you have been sent to us for MOHS surgery is that other forms of treatment have failed, or have a high chance of failure because of the cell type of the tumor. This does not mean that you are cancer prone or that you are a hopeless case. It merely means that the methods used to treat you in the past were not effective enough to destroy all of your skin cancer cells. Because MOHS surgery uses complete systematic microscopic control to search out the roots of the cancer, it has a much higher rate of cure than other methods even when skin cancer has persisted in spite of several other treatments.