HOW THE MOHS PROCEDURE WORKS...
Our surgeons remove the cancer layer by layer, examining each one microscopically until the margin around the cancer is free of cancer cells. This is a technically precise process in which the physician serves both as the surgeon and pathologist.
The Key steps in the procedure:
Surgical removal of the skin cancer is performed.
- The surgical site is washed and a local anesthesia is injected into the surgery site. (diagram 1)
- Fine surgical instruments are used to remove the visible cancer. Often times this is done by scraping because cancer cells are softer in texture than your normal skin and scrape away easily. (diagram 2)
- A thin layer of normal appearing skin surrounding the tumor is removed in hopes of getting a "cancer free" margin. This Is generally only 1-2mm around the tumor. (diagram 3)
- A map is drawn of the tissue specimen that was removed from the patient. (diagram 4)
- The tissue is dyed different colors to orient top to bottom and left to right. This is recorded on the map.
- The tissue is frozen and cut into thin pieces 1/10 the thickness of a piece of paper. (diagram 5)
- The thin pieces of tissue are placed on slides and dyed a second time so the cancer cells are visible under the microscope.
- The physician looks at the slides and determines if the cancer has been completely removed (diagram 6)
- If cancer remains, the physician marks on the map where the tumor is still present. (diagram 7)
- Due to the "mapping" technique, the doctor is able to remove only the cancer and preserve healthy tissue keeping the wound as small as possible.
Once the cancer is completely removed, reconstruction to give the best cosmetic outcome of the affected area is performed
- There are several reconstruction techniques depending on the size and location of the wound. A small simple wound may be allowed to heal on its own. A slightly larger wound may be closed with stitches, Larger wounds may require a skin graft or flap.
- The size of the scar depends on the size of the tumor. It is often difficult to predict the size of the tumor prior to surgery.
- Mohs surgeons are highly trained in reconstruction techniques and we perform 99% of the Mohs reconstructions in our office. However, in certain circumstances, a defect may become too large or invasive for us to properly close the wound. In order to best take care of the patient a specialized surgeon may be used to assist with reconstruction.
Step 1: The roots of a skin cancer may extend beyond the visible portion of the tumor. If these roots are not removed, the cancer will recur.
Step 2: The visible tumor is surgically removed.
Step 3: A layer of skin is removed and divided into sections. The ACMS surgeon then color codes each of these sections with dyes and makes reference marks on the skin to show the source of these sections. A map of the surgical site is then drawn.
Step 4: The undersurface and edges of each section are microscopically examined for evidence of remaining cancer.
Step 5: If cancer cells are found under the microscope, the ACMS surgeon marks their location onto the "map" and returns to the patient to remove another layer of skin - but only from precisely where the cancer cells remain.
Step 6: The removal process stops when there is no longer any evidence of cancer remaining in the surgical site. Because Mohs surgey removes only tissue containing cancer, it ensures that the maximum amount of healthy tissue is kept intact.