There are five standard methods for the treatment of skin cancers. The two non-surgical treatments are cryotherapy (deep freezing) and radiation therapy. The three surgical methods include simple excision, physical destruction (curettage with eletrodesiccation) and Mohs Micrographic Surgery. Newer methods under investigation include photodynamic therapy and immunochemotherapy.
In 1935, Dr. Frederic Mohs developed a technique for cancer removal known as chemosurgery. Originally, chemicals were applied to the skin during the surgery. These chemicals are now rarely used, but the name Mohs chemosurgery continues to be associated with the procedure now correctly termed Mohs Micrographic Surgery.
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 base of the site. This layer is generally only 1-2mm larger than the clinical tumor. Next, this tissue is mapped and processed in a unique manner and examined under the microscope. Our doctors examine the entire bottom surface and outside edges of the tissue on the microscopic slides. (This differs from the "frozen sections" prepared in a hospital setting which, in fact, represent 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 microscopic examination is then repeated. The entire process is repeated until no tumor is found.
Mohs Microsurgery allows for the selective removal of the skin cancer with the preservation of as much of the surrounding normal tissue as is possible. Because of this complete systematic microscopic search for the "roots" of the skin cancer, Mohs Micrographic Surgery offers the highest chance for complete removal of the cancer while sparing the normal tissue. The cure rate for new basal cell and squamous cell carcinomas exceeds 98%. 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.
An injection numbs the area. The visible portion of the tumor is debulked.
A thin layer of tissue is excised from the surrounding skin and base. The removal tissue is mapped and sectioned.
The deep and peripheral margins of each section are thinly sliced with a microtome and mounted on microscope slides for examination.
If additional tumor is found, it is located on the map, marked and removed. The examination/removal process continues until no tumor is found.