Mohs Surgery

About

Mohs surgery is usually done as an outpatient procedure using a local anesthetic, with oral sedation if requested. During Mohs surgery, a thin layer of tissue is removed and examined for cancer. The surgeon repeats the process as many times as necessary until the cancer cells are gone.

Multiple lesions can be done in one surgical session. Reconstruction (if needed) is routinely performed the same day, usually by the dermatology surgeon, but when necessary, with the help of other surgical specialists.

Step 1 – tumor removal

Step 2 – margin of tissue removed

Step 1

The tumor that the doctor can see (visible tumor) and a thin layer of surrounding tissue are removed. The image shows how tumor cells not visible to the eye may extend like a root down into the skin.

Step 2

After the visible tumor is removed, the surgeon removes another, wider margin of tissue for examination under a microscope. Remaining tumor cells (dark spot in the drawing) can be seen under the microscope.

Step 3

Step 3 – mapping tissue

Step 4 – tissue sample placed on slide

Tissue is marked and mapped to show the precise way it fit into the removal site. Marking helps the surgeon track the exact location of each piece of tissue.

Step 4

The tissue sample is flattened, thinly sliced and placed on a slide for viewing under the microscope.

Step 5

The sample is carefully examined for the presence of tumor cells.

Step 6

If the examination reveals more tumor cells, more tissue is removed. Tissue mapping shows the surgeon exactly what to remove. The process is repeated until the tissue is clear of cancer cells.

Step 5 – microscopic examination

Step 6 – removal of additional tissue

Once all skin cancer has been removed, the doctor will review the options for repairing the wound. The best method for healing depends on the size, shape and depth of the area where tissue was removed. Usually the dermatology surgeon either repairs the wound or allows it to heal by itself. In some cases, a surgeon who specializes in ophthalmoplastics, ENT or plastic and reconstructive surgery may be involved in repairing the wound.