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Mohs Surgery

Mohs surgery for skin cancer at the Dignity Health – Cancer Institute at St. Joseph's Hospital and Medical Center is a procedure originally developed in 1938 by a surgeon named Frederic Mohs and has advanced into the most effective treatment for the majority of skin cancers. The Mohs technique allows physicians to precisely identify and surgically excise an entire tumor while leaving the surrounding healthy skin intact and unharmed and having the opportunity to repair the surgical site almost immediately after the procedure.

According to the American College of Mohs Surgery (ACMS), a surgeon trained in the Mohs technique functions as a cancer surgeon, pathologist and reconstructive surgeon in one. That contributes to Mohs surgery having a success rate of just under 100 percent—the highest of all treatments for skin cancer.

Skin cancer is a significant problem in the U.S. The American Cancer Society reports that about 3.5 million cases of basal and squamous cell skin cancer are diagnosed each year. Melanoma, a potentially more aggressive type of skin cancer, accounts for more than 73,000 cases of skin cancer each year.

Mohs surgery, which can be used to treat basal cell and squamous cell carcinomas and even some cases of melanoma, typically is performed by a board-certified dermatologist trained in the Mohs technique. The procedure can be performed in an outpatient setting using local anesthesia.

Mohs Technique Effective and Efficient

With the Mohs procedure, skin cancer is surgically removed layer by layer. Each layer is examined under a microscope, while the patient remains in the surgical suite. When a layer of tissue is found to be cancer-free, that’s known as achieving “clear margins” and the cancer treatment portion of the procedure is considered finished. The repair of the surgical site typically follows.

The ACMS emphasizes that the advantages of Mohs surgery include:

  • ensuring total cancer removal during surgery, and almost completely eradicating the chance of the cancer returning;
  • minimizing healthy tissue lost;
  • maximizing function and cosmetic appearance after surgery; and
  • in most cases, mending the site of the cancer the same day of the surgery.

Other skin cancer treatment methods only estimate the amount of tissue to treat, which can result in unnecessary removal of healthy tissue and re-growth of the tumor if any cancer is missed.

Mohs surgery's high success rate means most patients require only a single surgery. Because Mohs surgery minimizes the amount of healthy tissue removed, it also reduces the impact to the surrounding areas of the body. The esthetic and cosmetic outcome of the surgery is optimized. Mohs surgery minimizes the risk of recurrence, and reduces and frequently eliminates the costs of more extensive and more serious surgeries.

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For more information about scheduling an appointment at the Dignity Health – Cancer Institute at St. Joseph's, please call (602) 406-8222.