6 Things Patients Should Know About Mohs Micrographic Surgery

Your first line of defense, of course, is avoiding skin cancer in the first place. Once you've been diagnosed with skin cancer, you have many options, even if Mohs surgery is not recommended in your case.

Mohs micrographic surgery is a precise, minimally invasive procedure used to treat certain types of skin cancer. Developed in the 1920s by Dr. Frederic Mohs, it remains one of the most effective treatments available today.

Most patients who undergo Mohs micrographic surgery are treated for basal cell carcinoma or squamous cell carcinoma, but the procedure can also be used for melanoma in situ (early-stage melanoma).

How is Mohs micrographic surgery different from regular surgery?

In standard skin cancer surgery, a tumor and some surrounding healthy skin are removed, but only a small sample of the tissue edges is examined under a microscope. That means cancer cells could remain undetected.

With Mohs micrographic surgery, 100% of the tissue margins are examined in real time. This ensures that all cancer is removed before the procedure ends, resulting in cure rates of 97–99%, far higher than conventional surgery. Mohs micrographic surgery is also done under local anesthesia in an outpatient clinic, so patients can go home the same day. 

What body parts is Mohs micrographic surgery best for removing skin cancer?

Mohs micrographic surgery is especially useful when conserving healthy tissue is important, such as on the face, scalp, ears, nose, lips, fingers, or genitals.

Who else benefits most from Mohs micrographic surgery?

It may also be recommended if you:

• Have a recurrent or incompletely removed tumor
• Have an early melanoma that’s difficult to detect
• Are elderly or medically fragile and better suited to local anesthesia

When is Mohs micrographic surgery not appropriate?

Mohs micrographic surgery is not used for every skin cancer. It may not be recommended if:

• The tumor is too small to consider Mohs micrographic surgery medically necessary
• The cancer has already spread (metastasized)
• The cancer type requires lymph node testing

Other skin cancer treatments may not be appropriate. Cryosurgery (cryotherapy) is a minimally invasive treatment that uses extreme cold to destroy abnormal or cancerous skin cells. It is effective for precancerous conditions like actinic keratosis and some early-stage skin cancers, including basal cell carcinoma and squamous cell carcinoma. Photodynamic therapy (PDT) is another option for precancerous lesions, using light plus a photosensitizing agent to treat and rejuvenate the skin. Excisional surgery, by contrast, removes both visible tumors and surrounding tissue to catch microscopic cancer cells.

What should I expect, before and after, Mohs micrographic surgery?

Most Mohs procedures take about three hours, though patients are usually advised to plan for a full day. Local anesthesia is used, so you’ll be awake but comfortable. Pain afterward is usually mild and managed with over-the-counter medication.

What are the risks of Mohs micrographic surgery?

Like any surgery, Mohs carries some risks, usually minor and only temporary:

• Mild pain
• Bleeding
• Infection

Mohs micrographic surgery combines high cure rates with maximum preservation of healthy tissue. What began as a multi-day process nearly 100 years ago is now a safe, same-day procedure — and one of the best tools we have for treating skin cancer.