You just found out the spot on your nose was a type of skin cancer that required a surgical technique called Mohs Surgery to remove it. What is Mohs surgery and why can’t your dermatologist tell you how long the procedure will take?
Both these questions are very good questions.
Mohs surgery is named for the physician who developed the technique, Dr. Frederic Mohs. It is an effective way for a dermatologist to remove skin cancer and preserve as much of the surrounding normal tissue as possible. During the first step in Mohs surgery your dermatologist removes the skin cancer lesion along with very little of the surrounding normal tissue. In most cases, you are immediately bandaged. The surgical technique to remove the tissue can take approximately 15-30 minutes. Most patients believe that is the end of the surgery. In fact, there are a few very important steps that need to be completed before you can go home.
The tissue that was removed must be processed by a Mohs Technician so that your dermatologist can determine whether or not any cancer cells remain. This is a slow process that can not be rushed. The tissue is carefully prepared to ensure all edges of the tissue will be visible when examined by your dermatologist. Next, the tissue is frozen and sliced into thin microscopic layers by a lab machine called a Cryostat. These thin layers of the tissue are then mounted on a slide and must dry. Once dried the specimen is stained using a specific order of stains and processing solutions. Now the tissue is ready to be examined by your dermatologist. The whole process of preparing the tissue takes approximately 45-60 minutes.
Your dermatologist will examine the processed tissue under a microscope to determine if any cancer cells remain. If the exam reveals cancerous cells in the tissue examined, a second layer will be removed and processed. In fact, multiple layers may be taken to ensure the area is free of cancer cells. Therefore, Mohs Surgery can take between 2-8 hours depending on the number of layers needed to remove all cancer cells.
Once the cancer cells are removed, your dermatologist will determine the best way to let the wound heal. If the wound is small and in a favorable location, it may be left to heal on its own. Frequently, a few stitches are all that is necessary after Mohs Surgery. Other times a larger area is involved and your dermatologist will use other procedures to reconstruct the area where the cancer was removed. The process of “closing” the wound may take approximately 30 minutes or more.
Mohs surgery is a very specific technique that requires multiple steps to ensure skin cancers are removed. You should expect your Mohs surgery to be completed within a couple of hours, although be prepared for the procedure to take longer. Most dermatologists offer a special area with a television to help patients pass the time. You may want to bring a book, a family member or a good friend to make your time as pleasant as possible.