What is Mohs Surgery?
There are five standard methods for treatment of skin cancers. The two nonsurgical treatments are cryotherapy (deep freezing) and radiation therapy. The three surgical methods include simple excision, physical destruction (curettage with electrodesiccation) and Mohs micrographic surgery. Newer methods under investigation include photodynamic therapy and immunochemotherapy.
In the past, Mohs Micrographic Surgery was sometimes called chemosurgery or Mohs chemosurgery. Originally, chemicals were applied to the skin during the surgery and hence, the name chemosurgery. Chemicals are now rarely used, but the name chemosurgery continues to be associated with the procedure.
After the removal of the visible portion of the tumor by excision or curettage (debulking) there are two basic steps to each Mohs Micrographic Surgery stage. First, a thin layer of tissue is surgically excised from the site. This layer is generally only 1-2 mm larger than the clinical tumor. Next, the tissue is processed in a unique manner and examined underneath the microscope. On the microscopic slides, Dr. Conti or Dr. Kozic examines the entire bottom surface and outside edges of the tissue. (This differs from the “frozen sections” prepared in a hospital setting which, represents only a tiny sampling of the tumor margins.) This tissue has been marked to orient top to bottom and left to right. If any tumor is seen during the microscopic examination, its location is established, and a thin layer of additional tissue is excised from the involved area. The micropscopic examination is then repeated. The entire process is repeated until no tumor is found.
Mohs Micrographic Surgery allows for the selective removal of the skin cancer with the preservation of as much of the surrounding normal tissue as possible. Because of this complete systematic microscopic search for the “roots” of the skin cancer, Mohs Micrographic Surgery offers the highest chance of complete removal of the cancer while sparing the normal tissue. The cure rate for new skin cancers exceeds 97%. As a result, Mohs Micrographic Surgery is very useful for large tumors, tumors with indistinct borders, tumors near vital functional or cosmetic structures, and tumors for which other forms of therapy have failed. No surgeon or technique can guarantee 100% chance of cure.
For more information, visit the American Society for Mohs Surgery at http://www.mohssurgery.org
What is Skin Cancer?
Skin Cancer is by far the most common malignant tumor in humans. The most common types of skin cancer are basal cell carcinoma, squamous cell carcinoma, and melanoma. Both basal cell carcinoma and squamous cell carcinoma begin as a single point in the upper layers of the skin and slowly enlarge, spreading both along the surface and downward. These extensions cannot always be directly seen. The tumor often extends far beyond what is visible on the surface of the skin. If not completely removed, both types of skin cancer may invade and destroy structures in their path. Although these skin cancers are locally destructive, they do not tend to metastasize (spread) to distant parts of the body. Metastasis of basal cell carcinoma is extremely rare and usually occurs only in the setting of long-standing large tumors where the patient’s immune system is compromised. Squamous cell carcinoma is slightly more dangerous, and patients must be observed for any spread of the tumor. Such spread is still infrequent. Melanoma is a very different and more dangerous kind of skin cancer and is occasionally treated with Mohs Micrographic Surgery.
Excessive exposure to sunlight is the single most important factor associated with the development of skin cancers. In addition, the tendency to develop these cancers appears to be hereditary in certain ethnic groups, especially those with fair complexions and poor tanning abilities. Fair skinned people develop skin cancers more frequently than dark skinned people, and the more sun exposure they receive, the more likely they are to develop a skin cancer. Other factors, including exposure to radiation, trauma and exposure to certain chemicals, may also be involved in the development of skin cancers.
The vast majority of skin cancers are present for more than a year before being diagnosed and their growth is rather slow. Skin cancers may be more aggressive in certain instances; patients whose immune system is compromised, patients with a medical history of leukemia or lymphoma, cancers in certain locations such as the ear, lips, lower nose, or around the eyes.
Click the link below to view Mohs College patient education video: