Advance with MUSC Health

Mohs Surgery: The Most Common Skin Cancer Treatment

Joseph Gerald (Jerry) Reves, M.D.
July 19, 2023
Person applyiing sunscreen to face

Skin cancer develops as we grow older because of years of exposure to ultraviolet light (UV) and the normal changes associated with aging. Skin cancer is the most common cancer in the United States. For those who live in areas with lots of sunshine or work outside, the exposure to UV light is increased, and the result can lead to skin cancer. The incidence is 20% overall in the American population, and the rate increases as we age.

Almost 10,000 Americans are diagnosed with skin cancer every year. There are two types of skin cancer: melanoma and non-melanoma. Melanoma is more deadly but less common than nonmelanoma. The most common nonmelanoma skin cancers are squamous cell and basal cell cancer.

There are at least 3 million new cases of these cancers every year in the United States.

Nonmelanoma Skin Cancer Risk Factors

  • Age + Gender: Up to age 50, women are at higher risk of developing skin cancer, but after that, men surpass women.
  • Skin tone + hair color: Light-skinned, blonde, or red-headed people are affected more frequently.
  • Personal history: A history of sunburns’ burn-and-peel cycle in childhood and repeated tanning-booth use, as well as a history of skin cancer, are risk factors. A history of five or more blistering sunburns between ages 15 and 20 significantly increases the risk of later skin cancer. This, of course, was common in our geriatric age group as we grew up before awareness of the need for and access to the good sunscreens and sun-protective garments available today.

Detecting Skin Cancer

A requirement for healthy aging is self-awareness of change. This goes for any symptom, and we should systematically look at our skin regularly — at least monthly — to note any changes.

Normal aging causes many changes, but the changes to look for are any increase in size, shape, or color of a “spot” or lesion of the skin. This should raise suspicion and requires immediate assessment by either your general practitioner or a dermatologist.

The earlier the detection of cancer, the better the chances are of a cure.

If a new sore develops but does not disappear in a month or so, it needs to be investigated.

Itching or bleeding from the site is another indication that it may be abnormal.

Skin Cancer Prevention

We have written about prevention before. The goal is to limit UV light exposure by mitigating sun exposure and avoiding tanning booths.

  • Sun-protective clothing: When outside, stay in the shade and wear protective clothing, including pants and long-sleeved shirts that advertise UV protection. These garments, which are made of lightweight material, are effective.
  • Sunscreen: Sunscreen of at least 30 SPF is an absolute requirement when planning to be in the sun for more than 15 minutes. Sunscreen must be reapplied at intervals to maintain protection, especially if perspiring, swimming, or in conditions that remove the application.
  • Hats: A wide-brimmed hat and sunglasses also enhance protection.

Skin Cancer Diagnosis

How is skin cancer diagnosed? Most skin cancers are diagnosed by a dermatologist. The typical diagnosis involves an excisional biopsy of the lesion at the time of a diagnostic appointment. The tissue sample is sent to a pathologist for interpretation. Usually, within a week, the pathology report confirms the absence or presence of cancer.

If cancer is present, you and your dermatologist then decide on the best treatment. Most nonmelanoma cancers are treated by surgery to remove the cancer.

Mohs surgery is the most common approach to typical squamous and basal cell cancers. Mohs surgery is performed as an outpatient procedure by specially trained dermatologic surgeons.

What is Mohs Surgery Treatment?

Mohs can mean “micrographically oriented histographic surgery,” although it is named after Dr. Frederick Mohs, who developed the procedure in the 1930s. Using local anesthesia, the surgeon removes the cancer in steps.

Here are a few things you should know about Mohs surgery:

  • It is best to reserve the entire day because the procedure does involve several hours of intermittent steps of surgery, specimen analysis, and further surgery until the cancer is removed and the specimen is clear.
  • When the onsite pathologic examination reveals that the margins of the excisional sample are free of cancer, no further tissue excision is needed. The Mohs surgeon will then close the incision with sutures using plastic-surgery techniques to minimize scarring and other site sequelae.
  • An adjacent “flap” of skin may be used to cover the site. If the site is large and located where there is not sufficient skin for primary closure or a flap, a skin graft is used to aid in healing. This requires the removal of skin from a donor site, such as the thigh, that is transferred to the site to cover the cavity, which will then heal under the protective skin cover.
  • Depending on the size and complexity of the surgery, the surgeon may prescribe medicines such as topical antibiotic ointments, oral antibiotics, and analgesics for pain may.
  • Wound care instructions are also provided.
  • A follow-up appointment with the Mohs surgeon is scheduled in about a week to ensure that healing is progressing.
  • In about 98% of cases, the cancer is cured, but the patient will need follow-up at specified intervals for examination of the site and other possible cancerous places.
  • Mohs surgery is safe, but it does have risks that include bleeding at the site or within the wound, forming a hematoma.
  • Pain, tenderness, and discomfort are common and may require treatment. Less common problems can be infection, temporary numbness at the site, shooting pain to other locations, and a thick, raised scar.

The Bottom Line

As we age, skin cancers are an increasing threat to our health. Regular skin surveillance and protection against the sun’s UV rays are required. Nevertheless, skin cancer is commonly detected, and it is important to have it diagnosed and treated as early as possible. Early detection and treatment with Mohs surgery should cure the most common nonmelanoma cancers.

Want to talk to a primary care provider about your skin cancer risk factors? You can schedule an appointment online or by calling 843-792-7000.