What is Mohs Micrographic Surgery?

Mohs Micrographic Surgery was named in honor of Dr. Fredrick Mohs, the physician who developed the basic technique over 50 years ago. Since Dr. Mohs first described this surgical procedure, many technical improvements and refinements have contributed to making it a safe and highly effective means of treating skin malignancies. The main difference between Mohs Surgery and other methods of removing skin cancers is meticulous microscopic control.

Mohs Micrographic Surgery, also called Mohs Surgery, chemosurgery, microscopically controlled surgery or histographic surgery, is a specialized technique where multiple horizontal layers of the skin cancer are removed. The success rate for Mohs Surgery in treating recurrent and/or aggressive cancers is 95% or better. Mohs Surgery requires a highly trained team of medical personnel, including a physician, nurse and technician. It is typically utilized for skin cancers that:

  • Are large and difficult to treat with other therapies.
  • Are located in high-risk areas such as the nose, ear and lip or around the eye.
  • Show an aggressive or infiltrative growth pattern when viewed under a microscope.
  • Are ill defined.

As the skin cancer is surgically removed, each section of skin is carefully identified and mapped by the surgeon so its exact location can be pinpointed on the patient’s body.

  • Every layer of tissue removed is inspected under a microscope for evidence of cancer cells.
  • If cancer cells are seen anywhere within the specimen, the Mohs surgeon continues to remove and examine sequential tissue layers, but only from that section of the wound.
  • If any cancer cells remain, the surgeon is able to locate them based on the mapping technique.
  • Subsequent layers of tissue are removed and the procedure is repeated until the physician is satisfied that the entire base and sides are clear of cancer cells.

In addition to ensuring total removal of the cancer, this process preserves as much normal healthy skin and tissue as possible. However, even with this meticulous surgical technique, rare recurrences may occur.