Mohs Surgery Information

What is Skin Cancer?

Skin cancer is the most prevalent of all cancers. More than one million Americans develop skin cancer every year. While most cells in the body divide and reproduce in an orderly manner at a slow pace, cancer occurs when there is abnormal growth of cells at an uncontrolled and unpredictable rate. The cancer tissue usually grows at the expense of surrounding normal tissue. In the skin, the most common types of cancer are basal cell carcinoma and squamous cell carcinoma.

There are also precancerous skin conditions, including actinic keratones, which can be removed by laser surgery, cryotherapy (freezing), chemical peeling, photodynamic therapy (PDT), dermabrasion, or other surgical procedures.

The leading cause of skin cancer is tanning (both in natural light and tanning beds) and overexposure to sunlight. This is why cancers develop most often on sun-exposed areas of the skin or areas exposed to tanning beds. Tanning booths emit UVA rays which damage skin’s DNA and may leave you at an increased risk for skin cancer. Skin cancer more commonly occurs in fair-skinned individuals and is more common in the southern “sunbelt” areas of the United States.

Basal Cell Carcinoma (BCC) and Squamous Cell Carcinoma (SCC)

Basal cell carcinomas are the most common type of skin cancer with over one million new cases a year. They originate in the base, or bottom, layer of the epidermis and usually appear as a small fleshy bump or nodule on the head, neck and hands or as red patches on the trunk. They don’t spread quickly and can take months or years to reach one-half inch in diameter. Untreated, the lesion will bleed, crust over, heal and repeat the cycle. This type of cancer rarely spreads to other parts of the body (metastasize) but it can extend below the skin to the bone and cause damage to the surrounding tissue.

Squamous cell carcinoma is the second most common skin cancer and is usually found on the ear, face, lips and mouth. It may appear as a bump or red, scaly patch. Squamous cell carcinomas can be more serious than basal cell carcinoma because they can develop into large masses and metastasize (or spread) to distant areas of the body. The abnormal cells originate in the uppermost areas of the skin and grow downward, forming a root and fingerlike projections under the surface of the skin. Unfortunately, at times these roots are so subtle they cannot be seen without the aid of a microscope. Thus, what you see on the surface of your skin is often only a small portion of t the total tumor.

There are several different types of basal and squamous cell carcinomas. It is important to determine the subtype prior to treatment, as different therapies may be required. Because of this, a biopsy is usually performed prior to treatment. If found early and treated properly, the cure rate by dermatology surgery for both basal cell and squamous cell carcinoma is 95%.


Melanoma is the deadliest skin cancer, accounting for two-thirds of all deaths attributed to skin cancers. It is projected that 44,000 Americans will develop melanoma this year. Melanoma starts in melanocytes (skin cells that produce melanin). Melanin is what makes the skin tan. Melanoma cells usually continue to produce melanin resulting in mixed shades of tan, brown, black, red or white. Melanoma usually spreads quickly and early detection is key. Melanoma may appear suddenly or may begin near a mole or other dark spot in the skin. It is important to know the location, size, and color of moles on your body so you can detect the changes. It is essential to have any change examined and/or treated by your dermatologist.

The ABCDE’s of melanoma are a good tool to use in periodic self-examinations.

  • Asymmetry - One half doesn’t match the other
  • Border Irregularity - The edges are ragged, notched or blurred.
  • Color - The pigmentation is not uniform.  Shades of tan, brown and black are present.  Dashes of red, white and blue add to the mottled appearance
  • Diameter - The width is greater than six millimeters (about the size of a pencil eraser).  Any growth of a mole should be a concern.
  • Evolving - Any change in color or borders need to be evaluated by a dermatologist.

The standard treatment for melanoma is surgical removal of the melanoma and a wide area of normal appearing skin surrounding the melanoma. However, there are special cases, especially on the head and neck region, where Mohs micrographic surgery is beneficial. Many of the melanomas in this region have poorly defined borders making standard excision difficult. Because of this, Mohs surgery is modified. The initial stages are performed using frozen tissue specimens as with other skin cancers. After the standard Mohs surgery is performed, however, an additional rim of tissue is removed for further histologic evaluation that may take a few days to process. The additional rim allows for more precise treatment of the melanoma. The reconstruction will be delayed until the final rim of tissue is cancer free.

How successful is the treatment of Skin Cancer?

Initial surgical treatment of skin cancer has a success rate of greater than 90%. Methods that are commonly used to treat skin cancer include excision, curettage and electrodessication (scraping and burning with an electric needle), cryosurgery, and radiation therapy. The method chosen depends on several factors, including the microscopic subtype of tumor, the location and size of the tumor, and previous therapy. You may have had one or more of these treatments before coming for Mohs surgery.

If a skin cancer that has been previously treated by one of the above techniques recurs, re-treatment with one of these methods has a success rate of less than 75%. The success rate of Mohs micrographic surgery is 97-98%.

Unlike other methods of treatment, Mohs surgery does not rely on surface inspection of the skin to judge the extent of cancer growth. If the tumor is not well defined, blending into the normal skin with unclear margins, or if it is growing within a scar from a previous surgery, too little tissue may be removed leaving a tumor behind or too much tissue may be removed. This could lead to tumor recurrence or unacceptable scarring. Mohs surgery allows the surgeon to trace out the margin of the tumor with the use of a microscope so that only the diseased tissue is removed, which results in higher cure rates, smaller defects, and better cosmetic outcomes.

There are several situations in which Mohs surgery is indicated:

  • When a tumor is in an area of the body where it is not effectively curablewith other methods
  • When a tumor is located on a structure that is so important that is so important that one wishes to spare as much of the normal skin as possible, such as on the face including the nose, eyelids, lips or ears.
  • When the extent of the tumor cannot be easily defined by visual inspection.
  • When the cancer has recurred after a previous treatment.

What is Mohs Surgery?

In the early 1940s, Dr Fredrick Mohs, professor of surgery at the Medial College of Wisconsin, developed a form of skin cancer treatment that he called “chemosurgery.” When chemosurgery was initially introduced, a chemical (zinc chloride) was applied to the tumor, which fixed the tissue prior to its removal. Since this time the procedure has bee refined and improved so that the procedure is now performed using frozen tissue without the use of a chemical paste. The name Mohs surgery, short for Mohs micrographic surgery, was adopted to honor Dr. Mohs for developing the technique.

The Mohs surgical team includes specially trained physicians, nurses, medical assistants, and histology technicians. The phuysician leading the team is fellowship trained and is recognized by the American College of Mohs Micrographic surgery. Nurses and medical assistants are important members of the team who help answer your questions, respond to your anxieties, assist in surgery, apply dressings and instruct you in the after surgery wound care. A histology technician performs the important task of preparing the tissue slides, which are examined under a microscope by the Mohs surgeon.

Mohs surgery is a highly specialized technique that combines the surgical removal of skin cancer with immediate microscopic examination of the tissue by the Mohs surgeon to identify the presence of any residual cancer. The area around the suspected skin cancer is injected with local anesthesia so that there is no pain during the removal. The tumor is then scraped with an instrument called a curette to remove most of the visible cancer. A disc-shaped piece of tissue is then removed with a scalpel around and underneath the scraped area and carefully divided into sections. The edges are marked with colored inks and a careful map of the removed tissue is made. The tissue is submitted to the histotechnician for frozen sectioning and processing. Bleeding is controlled using pressure and electro cautery. A pressure dressing is applied and the patient is then escorted to the waiting area while the tissue is processed. The Mohs surgeon then examines the tissue under the microscope. If cancer cells remain, they are located by referring to the tissue map. Another section of tissue is removed and the procedure is repeated until no cancer is remaining. This process ensures total removal of the cancer while preserving as much of the normal healthy tissue surrounding the tumor as possible.

The removal and processing of each layer of tissue takes approximately one hour. Only 20-30 minutes is spent in the actual surgical procedure, the remaining time is required for slide preparation and interpretation. It usually takes two or three stages to complete the surgery. Surgery is usually started early in the morning and finished in one day. Occasionally, the tumor is extensive enough to necessitate continuing surgery on the second day. When Mohs surgery is complete, you will be left with a surgical wound that will be reconstructed following removal of the tumor. Because normal skin is preserved to the greatest extent possible, the best cosmetic results are possible. While the appearance of a scar will be minimized, you will be left with a scar. Several reconstructive options will be discussed with you in order to provide the best possible cosmetic results.

Reconstructive options

  • Healing by granulation involves allowing the wound to heal without suturing.  Experience has taught us that there are certain areas of the body where nature will heal wounds better than other reconstructive options.  There are also instances when a wound is allowed to heal on its own for a period of time before a reconstructive procedure is planned.
  • Suturing the wound is primarily performed on small to medium-sized wounds.  This involves some adjustment of the wound and suturing of the skin edges with a combination of deep and superficial sutures.  Healing is usually faster and can offer a good cosmetic result.  For example, the scar may be placed along a wrinkle line; however, the scar may be longer than you may have expected.
  • Skin grafts involve covering the wound with skin from another area.  The skin is usually removed from around the ear, the neck or the clavicle, which is then sutured together to provide a good cosmetic result.
  • Skin flaps involve movement of adjacent healthy skin to cover the wound.  Where practical, skin flaps are chosen because of the excellent cosmetic match of nearby skin and the ability to close wounds that cannot be closed in a side to side manner without producing distortion of anatomic structures or excessive tension on the skin edges.

How Do I Prepare for the Day of Surgery?

Dr. Campbell will schedule a consultation prior to surgery or our staff will contact you regarding the date and time of the procedure. At the consultation, your surgery will be discussed in detail, a biopsy may be performed if it has not already been done, and the necessary paperwork will be completed. If you are coming from a great distance away or are referred from a physician who is familiar with Mohs surgery, you may be marked for surgery without a preoperative visit.

Unless prescribed by your physician, we ask that you avoid all aspirin, ibuprofen, NSAIDs, fish oil, and aspirin-containing drugs for 14 days prior to surgery. Other herbal medications that affect bleeding include vitamin E, ginko biloba, and garlic. Alcohol will also increase bleeding and should be avoided for one week prior to your surgery. If you take blood thinners (i.e. Coumadin, Aspirin, Plavix) for medical conditions continue to take the medication, but please let our team know when you schedule your surgery.

The morning of surgery you may be given anti-anxiety medication if you are feeling anxious. Make-up, moisturizers, perfume, cologne and jewelry should NOT be worn. Also, be sure to wear comfortable clothing. A shirt that buttons rather than one that slips over the head is best. You may want to shower or wash your hair prior to surgery, as bandages may need to be kept dry for 1 to 5 days following the surgery. You will be in the office most of the day; therefore, you may want to bring a snack or sandwich. Please bring a book or something to during the waiting period. Once the surgery has begun, you will need to remain in the office. Also, because the day may probe to be quite tiring, it is good to have someone accompany you to provide companionship and possible driving assistance after your surgery.

Most insurance carriers cover the cost of Mohs surgery and reconstruction. Please be prepared to provide your insurance information to our billing office and bring with you any forms that may need processing. If your insurance requires pre-approval, please help us to make sure this is in the place prior to your surgery.

What Happens the Day of Surgery?

Your appointment has been purposefully scheduled early in the day. Upon arrival you may check in at the registration desk, and when the surgical suite is available our medical assistant will bring you back. If you have not had a consultation, Dr. Campbell will review the procedure with you, review your health questionnaire, and answer any questions that you may have.

After all of your questions have been answered and the correct site has been confirmed, photographs are taken of the surgery site, the skin is cleansed and the numbing medication is injected. After the area is numbed, the tumor will be removed. This issue usually only takes a short time. After the tumor is removed, a temporary bandage is applied and you will return to the waiting room while the tissue is being processed. The processing of the tissue usually takes 1-2 hours. If more tumor removal is required the entire process is repeated. Once Dr. Campbell is certain that the entire tumor has been removed, she will discuss with you what kind of reconstructive surgery, if any is necessary. If reconstructive surgery is needed, it is usually performed on the same day. Once all surgery is completed, a bandage will be applied and all instructions for care will be explained. You will also be given a wound care instruction sheet and will be scheduled to return in one week for a surgical follow up.

What Can I Expect After the Surgery?

For most cases, the surgery area is cleaned daily with tap water and then Vaseline ointment (please obtain a tube found in the baby aisle in most drugstores) is applied with a clean Q-tip.  It is likely that you will need to refrain from strenuous activity for 1-2 weeks following the surgery.  Appointments for follow up and possible suture removal in 5-7 days may be scheduled.  If you live out of town, this follow up appointment may be arranged with your local physician.  Additional check-ups may be recommended.


Most people are concerned about pain.  The majority of people will experience little discomfort after surgery.  Tylenol is recommended for pain and, if needed, a stronger pain reliever can be prescribed.


A small number of patients will experience some post-operative bleeding.  It can usually be controlled by applying pressure to the wound.  If bleeding persists, Dr. Campbell can be reached by contacting the number provided from the practice where the surgery was performed.


There are some minor complications that may occur after Mohs surgery. A small red area may develop around your wound. This is normal and does not necessarily indicate infection. If the redness does not subside within two days or the wound begins to drain notify us immediately.

Swelling and bruising are very common following Mohs surgery, especially in areas around the eyes and mouth. Elevation and frequent applications of ice are important to minimize swelling which usually lasts for the first week after surgery.

Itching and redness around the wound, especially in areas under adhesive tape, are not uncommon. If this occurs, ask your pharmacist for a non-allergic tape and let us know at your follow-up visit.

Occasionally the area around the surgical site may feel numb to the touch. This may persist for several months or longer. In some instances this may be permanent. If this occurs, discuss it during your follow-up visit.

Although every effort will be made to offer the best possible cosmetic result, you will be left with a scar. The scar can be minimized by the proper care of your wound. You will be provided with detailed wound instructions that will be reviewed with you after your surgery. It is important to follow these instructions carefully to optimize your cosmetic outcome.

Will I Develop More Skin Cancers?

After having skin cancer, statistics say that you have a higher chance of developing a second skin cancer.  The damage your skin has already received from the sun cannot be reversed.  However, precautions can be taken to prevent further damage that may contribute to additional skin cancers.  Protective measures include avoiding direct sunlight and excessive exposures especially during peak hours of 10:00am to 4:00pm, applying zinc oxide sunscreen at least 10 minutes before exposure and every two hours while in the sun, and wearing a wide brimmed hat and protective clothing on exposed areas.  Make sure your sunscreen has an SPF of 30 or greater and protects the skin from both ultraviolet B (UVB) rays, which cause the skin to burn, and UVA rays, which cause the skin to age.  The use of sunscreens with one of the following active ingredients is recommended:  titanium dioxide, zinc oxide, or avobenzone.  You should also perform self-skin exams regularly and have your skin examined by your dermatologist every six months.

Accessibility Toolbar

Scroll to Top