Mohs Micrographic Surgery


Approximately 70 years ago, Dr. Frederic Mohs developed a technique (known as chemosurgery) to remove skin cancers. This method requires highly specialized training and personnel, and the large number of cases which have been cured clearly demonstrates that Mohs surgery is a highly successful method of treatment for skin cancer.

What Is Mohs Surgery?

It is a highly specialized procedure for the total removal of skin cancers. It involves microscopically controlled excision of the cancer and graphic mapping of the lesions for orientation purposes. Thus the name, micrographic surgery, or Mohs surgery after its originator, Frederic Mohs.

About Our Staff

The Mohs Surgery team consists of several individuals who will serve you. The highly-trained surgeons that perform Mohs Micrographic Surgery are specialists both in dermatology and pathology. With their extensive knowledge of the skin and unique pathological skills, they are able to remove only diseased tissue, preserving healthy tissue and minimizing the cosmetic impact of the surgery. The American College of Mohs Surgery currently recognizes more than 60 training centers where qualified applicants receive comprehensive training in Mohs Micrographic Surgery. The minimum training period is one year during which the dermatologist acquires extensive experience in all aspects of Mohs Surgery, pathology and training in reconstructive Surgery.

In addition to the physician, the team includes medical staff experienced in dealing with patients who have skin cancer and are knowledgeable about possible problems which may arise. Another important member of the team is a technician who quickly and skillfully prepares the tissue for microscopic examination.

What is Skin Cancer?

Cancer is tissue which grows at an uncontrollable and unpredictable rate. In the skin, there are three main forms: basal cell carcinoma (or epithelioma), squamous cell carcinoma, and malignant melanoma. The names refer to the cell types form which these cancers are derived.

Is it Dangerous?

The most common types are basal cell carcinomas and squamous cell carcinomas. Both types enlarge from the point where they first occur and usually do not spread (metastasize) to distant parts of the body. If not completely removed, both could possibly invade and destroy adjacent structures such as the eye, ear or nose. Compared to other forms of cancer, these types of skin cancer are generally recognized in their early stages and are therefore more easily cured. Malignant melanoma, on the other hand, may be life-threatening if not treated early. It usually appears as a brownish-black spot or bump on the skin which enlarges and sometimes bleeds. Sometimes, but not always, melanomas arise in moles that have been present for many years.

What Causes Skin Cancer?

The cause of skin cancer, like other forms of cancer, is not completely known. Excessive exposure to sunlight is the single most important factor associated with the development of these skin cancers which appear most commonly on the face and arms (the most often sun exposed parts of the body).

Skin cancer also tends to be seen more often in certain ethnic groups, especially those with fair complexions. Thus, the tendency to develop skin cancer is inherited along with your type of complexion. Other possible causes of skin cancer include X-rays, trauma, and certain chemicals such as arsenic. There are studies going on today to elucidate these and other possible causes.

How Does Skin Cancer Start? How Does It Grow?

Skin cancer begins in the uppermost layer of the skin and invades downward with roots and to the sides on the surface of the skin. Unfortunately, these extensions cannot be directly visualized. What is apparent to the naked eye on the surface of the skin may actually be only the "tip of the iceberg".

How May Skin Cancer Be Treated?

There are several methods of treating skin cancer, all highly successful in the majority of patients. These methods include excision (surgical removal) and suturing (sewing), laser surgery, curettage and electrodessication (scraping and burning with an electrical needle), radiotherapy (X-ray), cryosurgery (freezing), topical chemotherapy (chemical destruction) and Mohs’ surgery (microscopically controlled excision). Which method we use depends on several factors, such as the type of skin cancer, the location of the cancer, the size of the skin cancer, and previous therapies of the skin cancer.

When is Mohs surgery recommended?

Most Mohs patients have a common type of skin cancer like basal cell carcinoma (BCC) or squamous cell carcinoma (SCC). Mohs is usually recommended when a BCC or SCC:

  • Is aggressive or large
  • Appears in an area with little tissue beneath it (e.g., eyelid, nose, ear, scalp, genitals, hand, or foot)
  • Was treated and has returned

Mohs is also used to treat some rare skin cancers like DFSP, extramammary Paget’s disease, and Merkel cell carcinoma.

Q & A

How Is Mohs Surgery Performed?

With advanced laboratory methods today, Mohs surgery involves three separate steps:

  1. Surgical excision done under local anesthesia
  2. Mapping of the excised tissue on paper for orientation purposes
  3. Examination of this excised tissue under the microscope. Before the tissue is examined, it is marked with colored dyes to distinguish top from bottom and right from left. By doing this, we are able to pinpoint the exact location of any remaining tumor during the microscopic examination. If more cancer is found, the entire procedure is repeated, but only in the area of the remaining cancer.

Only by the careful, cell-by-cell microscopic examination of the removed skin can one be certain as possible that no cancer remains.

How Long Does it Take?

Total removal of skin cancer, which may involve several surgical sessions, is usually completed in several hours to 1 day. After the surgery, a decision is made as to the best way to manage the wound created by the removal of the skin cancer. The length of time can depend on the number of stages and the complexity of the repair that is done.

How Effective is Mohs Surgery In The Treatment Of Skin Cancer?

Using Mohs technique, the percentage of success is very high, often 95-99%, even if other forms of treatment have failed. Thus, 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 therapy will leave a scar. By preserving as much normal skin as possible, the Mohs surgery technique tends to minimize the scar as much as possible.

What Are The Advantages Of Mohs Surgery?

The Mohs surgeon can pinpoint with the microscope the areas where there is cancer and selectively remove tissues only from those areas. In this way the skin cancer is traced out to its roots with little guesswork involved.

This results in:

  1. The removal of as little normal skin as possible.
  2. The highest chance of curing the patient.

Other forms of therapy frequently have only a 50-70% chance of success in curing skin cancers that have had previous treatment that failed.

Will My Insurance Reimburse Me For Mohs Surgery?

Some health insurance policies cover the total cost of Mohs surgery. Most cover at least part of it. Each policy is different. Please check with our billing office if you have any questions regarding costs and insurance forms.

How Should I Prepare Myself For Mohs Surgery

If you are taking blood thinners (anticoagulant; used to prevent blood clotting), please contact your doctor who prescribed the medication for instructions to determine if it is safe to stop taking the blood thinner 3 to 10 days prior to your surgery if possible. If you are taking a medication other than blood thinner, take it as usual unless we direct otherwise.

If you have heart valve disease, heart murmur, or an artificial hip or knee, you may need prophylactic treatment with antibiotic prior to surgery. Please let us know in advance if you have any of the above-mentioned conditions.

Try to get a good night’s rest, eat a light meal, and get to the office on time. It is a good idea to bring a book, newspaper, or magazine with you on the day of surgery. In some cases, the procedure may take up to a full day, most of which will be spent in the waiting room for your tissue to be processed and examined.

How Many Sessions Of Mohs Surgery Will I Need?

This depends entirely on how deep or extensive your skin cancer is. Unfortunately, there is no way to determine this prior to surgery.

How Long Does The Surgery Take?

Each step (or stage) of the surgical procedure usually takes only 15-30 MINUTES. However, after the surgery it usually takes about 45-60 MINUTES for the slides to be prepared for the physician to perform the complex microscopic examination. Several surgical stages and microscopic examinations may be required. In addition, a repair may be required and performed. Total time in the office can vary between 60 minutes for a small 1 stage case not requiring sutures to up to 6-8 hours for a complex case.

Does It Hurt?

A local anesthetic, usually Xylocaine (Lidocaine) and/or Marcaine (Bupivicaine), is injected around the skin cancer to numb the area. This is similar to the injection that the dentist may give you before he/she works on your teeth. The surgery does cause some discomfort, but no pain is felt once the anesthetic has been injected and takes effect.

Should Someone Come With Me On The Day Of Surgery? Do I Need Someone To Drive Me Home?

Yes, if possible, it is recommended that you have someone drive you home. It may be more pleasant for you to have company during your day.

If The Wound Is Allowed To Heal By Itself, What Is The Procedure?

If the wound is allowed to heal by natural processes (granulation or 2nd intention), it usually heals in 4 to 8 weeks. During this period of time, you will cleanse the wound 2-3 times a day. When healing is well advanced, you will be permitted to stop the dressing changes. If someone else will be doing the dressing changes for you, please bring that relative or friend with you on the day of your surgery in order that we may instruct them in the proper manner.

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Our Location

1501 Superior Ave Suite 115 Newport Beach, CA 92663 949-640-SKIN

Hours of Operation

Lunch Hour: 12pm-1pm


9:00 am-5:00 pm


9:00 am-5:00 pm


9:00 am-5:00 pm


9:00 am-5:00 pm


9:00 am-5:00 pm