Melanoma is the deadliest type of skin cancer, and it originates in pigment cells called melanocytes that are found in the epidermis. The danger of melanoma is due to its aggressiveness; it is more likely to metastasize or spread than are other skin cancers. It will often spread to the lymph system, various organs, or both. Catching it early is vital. Mohs surgery is one of the procedures that can be used to treat melanoma.
What Is Mohs Surgery?
Also known as Mohs micrographic surgery, Mohs surgery is a procedure used to remove skin cancer. It is most commonly used to treat basal cell carcinoma and squamous cell carcinoma, which are the two most common types of skin cancer. It is a well-established procedure that was developed by Dr. Frederic Mohs back in the 1930s.
Mohs surgery is extremely effective. It boasts a cure rate of 99 percent for new cancers and a cure rate of 95 percent for returning cancers. Mohs surgery also has the advantage of preserving more healthy tissue than a simple excision or surgical removal. In a standard excision, the doctor will remove the cancer plus a sizable margin of apparently healthy tissue. During Mohs surgery, the doctor will excise the tumor and a much smaller margin of healthy tissue.
What Happens During the Procedure?
The doctor will apply a local anesthetic to the treatment site and then excise the cancer. In a standard excision, the doctor would then send the tissue sample to a pathology lab for analysis. The patient would have to sweat at home while they waited to hear if the doctor had gotten all of the cancer or not.
By contrast, a doctor performing Mohs surgery will take the sample to an onsite lab and carefully prepare it for analysis. They will cut the sample into thin layers and examine each layer under a microscope looking for cancer cells. If they find some, they will make a note of the location and return to the patient to remove another tissue layer and examine that. They would repeat the process until all of the samples were cancer-free. Mohs surgery is thus a very painstaking process that can take hours. The patient, on the other hand, can go home knowing that they are cancer-free.
What Are Some of the Other Advantages of Mohs?
Mohs surgery is extremely safe. It does not require general anesthesia so patients who are unable to undergo conventional surgery may safely undergo Mohs. It is thus a good choice for elderly patients or those in very poor health.
Mohs surgery is extremely precise, so the resultant wound is smaller than that produced by conventional surgery. Consequently, there is also less scarring. That makes Mohs surgery a good procedure to use on highly visible parts of the body. In fact, about 90 percent of Mohs surgery procedures are done on the face. It can also be safely done on the hands and feet without reducing function by removing a lot of tissue.
Mohs surgery can be performed in a clinic or office suite. The patient thus won’t have to go to a hospital.
What Happens After the Surgery?
The size of the resulting wound will determine how the doctor closes it. If the wound is very small, the patient may need nothing more than a Band-Aid. A bigger wound will require stitches. Still larger wounds may require reconstruction in the form of a skin flap or flap graft. In such cases, the doctor may work with a plastic surgeon.
In all cases, the doctor will advise the patient on the best ways to take care of their wound in order to prevent scarring. If the patient needed stitches, they will visit the doctor about a week later to have them removed. The doctor will also examine the wound.
What Are the Stages?
When doctors talk about a cancer’s stages, they are describing how far it has progressed and whether or not it has metastasized. Doctors need to know what stage a cancer has reached in order to decide on a treatment.
Stages range from 0 to IV; the higher the number is, the worse the cancer is. Stage 0 is the earliest stage: The melanoma is small and is still confined to the epidermis. A Stage I melanoma has reached the dermis. While a Stage II melanoma is also confined to the dermis, it is bigger than a Stage I melanoma and may be about to metastasize. Stage III and Stage IV melanomas have metastasized.
When performing Mohs surgery, doctors use the stage system to decide how big the margin should be. In other words, they need to decide how much seemingly healthy tissue they should remove along with the cancer. As might be guessed, if the melanoma has been caught in an early stage, the doctor needs to remove only a little tissue – as little as 5 mm in some cases. If the patient has a late-stage melanoma, the doctor will remove more tissue to make certain they got all of the cancer. In the case of a late-stage melanoma, the doctor may remove as much as 2 cm (.8 in) of tissue around the cancer.
Doctors can also now use special stains to identify cancerous melanocytes that have spread beyond the margins. That means they can use Mohs surgery even in cases where the melanoma has metastasized, but they will generally have the patient undergo another therapy like radiation treatments or chemotherapy to make certain that they have killed all of the cancer cells.