Woman's back before a mole removal procedure at Saguaro Dermatology - Phoenix Dermatologist

Mohs Surgery

Mohs surgery was invented by Dr. Frederic Mohs at the University of Wisconsin. Here at Saguaro Dermatology, we are lucky to have two skilled Mohs Surgeons. Dr. Thaler trained with Dr. Mohs personally and is an excellent dermatologist and specialized skin cancer surgeon. Dr. Wald has specialized in skin cancer detection and treatment over the course of her career and completed a highly sought fellowship in Mohs Microscopic Surgery and Dermatologic Oncology at St. Vincent Hospital in Indiana. During her fellowship, she completed more than 1,700 surgeries and reconstructions.

Mohs Surgery (also called Mohs Micrographic Surgery) is a surgical treatment used to remove skin tumors and certain skin cancers (usually nonmelanoma skin cancers). Mohs Surgery is an out-patient procedure during which the cancerous tissue is excised (cut out or removed), frozen, sliced into layers, and analyzed immediately to detect whether all the cancer has been removed. It is performed with local anesthetic, so you will be awake during the actual surgery. The process of “cutting” and “checking” may be repeated until all cancerous tissue has been eliminated, so patients have very high cure rates.

What Cancers Is Mohs Surgery Used For?

Mohs surgery is used on certain skin cancers, especially high-risk basal cell and squamous cell carcinomas, and on many other rare or aggressive skin tumors as well. In fact, patients with basal cell carcinomas receive the most referrals for Mohs micrographic surgery, followed by patients with squamous cell carcinomas. These nonmelanoma skin cancers account for roughly one million cancer cases in the United States, and skin cancer accounts for more than 50 percent of all cancers in the United States. Historically, Mohs surgery has not been used to treat melanomas because suspected melanomas, such as atypical moles or skin lesions with uncommon pigmented features (melanocytic atypia), are difficult to assess with frozen sections. However, the procedure is increasingly used to treat some forms of melanoma skin cancers as well.

Is Mohs Surgery Used for Particular Sites on the Body?

Mohs surgery is performed on skin tumors or lesions of all sizes in sensitive sites, such as the eyelids, nose, ears, lips, fingers, and genitalia. Mohs surgery is the preferred treatment in these cases because the procedure has the highest cure rate, but also “spares” the tissue surrounding the cancerous site, often resulting in less damage and scarring.

Mohs surgery is also used on larger tumors because these carry more risk of returning and/or invading nearby nerve bundles and because simpler approaches are often less effective on these kinds of tumors. A tumor of about a quarter inch (6 mm) or more in diameter on the central face is considered high risk, as is a tumor measuring three quarters of an inch (20 mm) or more on the back. Mohs surgery is also used on tumors in sites where radiation therapy has been performed and on aggressive or unpredictable tumors in general.

The technique used in Mohs surgery involves several stages. After prepping and examining the tumor or lesion, the physician will surgically remove the visible tumor or layer of cancerous tissue. The removed tissue will be stained with ink so that it can be matched later to the site of removal. This specimen is then frozen and sliced into layers for examination under a microscope. The physician will be able to detect whether all cancerous tissue has been removed. If any cancerous tissue remains along the margins (edges) of the sample, the process will be repeated until the cancerous tissue has been completely removed. After that, depending on the size of the wound, it will be left open to heal or closed with stitches. Larger wounds can be repaired or reconstructed using a skin flap or skin graft.
As with any kind of surgical procedure, you may experience some postoperative bleeding and minor pain; swelling and bruising are also common in the days following the procedure. Discomfort is usually manageable, however, and can be treated with acetaminophen and, in the case of swelling, the use of an ice pack. If the wound has been stitched up, the sutures will be removed 5 to 14 days after surgery, depending on the site and the type of repair. You should limit vigorous exercise or physical activity for up to a week to prevent damage to the wound and loosening of the stitches.
Most Mohs surgeons are dermatologists. We believe it is best that your tumor or skin cancer be removed by a dermatologist with formal training and experience identifying and treating skin cancers, though there are non-dermatologist physicians who also perform the procedure. In some cases, a second specialist, such as a plastic surgeon, may assist with or perform the repair of the wound.
In addition to the kind of cancers mentioned above, Mohs surgery is also considered for skin cancer patients with weakened immune systems, or immunosuppression, because these individuals often develop more aggressive tumors with higher recurrence rates, particularly squamous cell carcinomas. Mohs surgery is also used to treat other less common skin tumors, including Merkel cell carcinoma and abnormal growths (neoplasms) in the sebaceous gland and hair follicle or from the sweat glands.

How Much Does Mohs Surgery Cost?

The cost of any medical procedure depends on the provider and kind of facility at which it is done—for example it is typically cheaper in a physician-owned private office compared to a hospital-owned outpatient surgical facility. Moreover, out-of-pocket costs vary greatly depending on the kind of insurance plan you have. You do have to pay for the “removal” and the “repair” separately because different repairs have different risks and difficulties. However, Mohs surgery is considered cost-effective compared with other treatments performed in an inpatient or outpatient setting, especially considering that it is the only procedure that includes the actual surgery, the pathology (lab work), anesthesia, and supply expenses (2). With Mohs surgery, it is not uncommon for a single payment to be made to a single provider. The staff at Saguaro Dermatology will be happy to explain billing for the procedure and to discuss all your options before scheduling.

Complications of Mohs surgery are similar to those of other outpatient surgical procedures (1). While some postoperative pain and bleeding are normal, hematoma (blood leaking from a blood vessel under the skin), necrosis (death of tissue) of the skin flap or graft, and wound infection are possible. Fortunately, wound infection develops in less than 3 percent of patients, generally occurs about 96 hours after surgery, and usually can be managed with oral antibiotics.
Recovery time after Mohs surgery depends on the size and location of the wound, the extent of reconstruction, and on how well you follow the instructions for care of the wound. For small wounds left open to heal by themselves, complete healing may take 4 to 6 weeks. The time frame is similar for more extensive wounds closed with sutures or for wounds requiring reconstruction, but it is important to keep scheduled follow-up appointments with your doctor to make sure you are healing properly.

The benefits of Mohs surgery include the following:

  • It aims for the highest possible rates of cure and minimizes tumor recurrence rates;
  • It produces precise results and is the most effective method of eradicating the most common types of skin cancer;
  • It minimizes the size of the wound and damage to the tissue around sensitive sites such as the eyes, nose, ears, and mouth;
  • It allows for more successful reconstruction of the affected tissue;
  • It preserves the function of the eyelids, nostrils, and tissues around the mouth and ears;
  • It is cost effective;
  • It requires only local anesthesia, which is safer and cheaper than general anesthesia

Mohs Surgery Before and After

Mohs Surgery Before and After

Final Word on Mohs Surgery

Mohs surgery is a safe, effective, and cost-efficient treatment for skin cancers and tumors. It has the highest cure rates and preserves the greatest amount of normal tissue. There is no wait time for lab results, and any necessary reconstruction can be performed immediately.  We are pleased to offer Mohs Surgery in Phoenix and Mesa, Arizona. We have two  very experienced dermatologic surgeons, Dr. Millard Thaler and Dr. Jenna Wald. For more information, talk to one of our friendly staff members at Saguaro Dermatology today.

Sources and Suggested Readings
“AAD/ACMS/ASDSA/ASMS 2012 appropriate use criteria for Mohs micrographic surgery: a report of the American Academy of Dermatology, American College of Mohs Surgery, American Society for Dermatologic Surgery Association, and the American Society for Mohs Surgery”. Journal of the American Academy of Dermatology. 67 (4): 531–50.doi:10.1016/j.jaad.2012.06.009PMID 22959232.

2 Tolkachjov SN, Brodland DG, Coldiron BM. Understanding Mohs Micrographic Surgery: A Review and Practical Guide for the Nondermatologist. Mayo Clin Proc 2017 Aug;92(8):1261-1271. doi: 10.1016/j.mayocp.2017.04.009. https://www.skincancer.org/treatment-resources/mohs-surgery/

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Saguaro Dermatology | Phoenix Dermatology

About Saguaro Dermatology

Our comprehensive dermatology clinic is dedicated to providing you with the highest quality of care, innovative practices, helpful resources and state-of-the-art technology to prevent and treat a multitude of skin disorders. Led by Carsten R. Hamann, MD, PhD, Dathan Hamann, MD, FAAD, Michael McBride, DO, Millard Thaler, MD, Mohs Surgeon and Jenna Wald, MD, Mohs Surgeon, our passionate team looks forward to serving you with respect and compassion.

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