Reference: www.aad.org
At Soderstrom Dermatology Center, S.C., we are proud to offer this highly effective skin cancer treatment to our patients who need it. Mohs micrographic surgery, an advanced treatment for skin cancer, offers the highest potential for cure -- even if the skin cancer has been previously treated. This procedure is a state-of-the-art treatment in which the physician serves as a surgeon, pathologist and reconstructive surgeon. It relies on the accuracy of a microscope to trace and ensure removal of skin cancer down to its roots. This procedure allows dermatologists, trained in Mohs surgery, to see beyond the visible disease. To precisely identify and remove the entire tumor, leaving healthy tissue intact and unharmed. Mohs surgery is most often used on treatment two of the most common forms of skin cancer: basal cell carcinoma and squamous cell carcinoma. It has also been proven extremely effective in the treatment of malignant melanomas.
Clinical studies have shown that the cure rate for Mohs micrographic surgery is the highest of all treatments for skin cancer - up to 99 percent, 5 year cure rate, even if other forms of treatment have failed - and 95 percent for recurrent cancer. As the most exact and precise method of tumor removal, this procedure minimizes the chance of regrowth and lessens the potential for scarring and disfigurement. As such, Mohs surgery offers the highest potential for complete removal of the cancer while sparing the surrounding healthy tissue.
Cost Effectiveness
In addition to its high cure rate, Mohs micrographic surgery has also been shown to be cost effective. In a study of costs of various types of skin cancer removal, the Mohs process was found to be comparable to the cost of other procedures, such as electrodissecation and curettage and cryosurgery. It is also less expensive than multiple repeated surgical procedures and radiation treatments can be 10-20 treatments in a series.
History
Developed by Frederic E. Mohs, M.D., in the 1930s, the Mohs micrographic surgical procedure has been refined and perfected for more than half a century. Initially, Dr. Mohs removed tumors with a chemosurgical technique. Over the course of a number of days, thin layers of tissue were excised and frozen before being pathologically examined. He developed a unique technique of color-coding excised specimens and created a mapping process to accurately identify the location of remaining cancerous cells.
As the process evolved, surgeons refined the technique and now excise the tumor, remove layers of tissue and examine the fresh tissue immediately. The normal treatment time has now been reduced to one visit and allows for immediate reconstruction of the wound. The heart of the procedure - the color-coded mapping of excised specimens and their thorough microscopic examination - remains the definitive part of the Mohs micrographic surgery.
Treatment Issues
Common treatment procedures sometimes prove ineffective because they rely on the human eye to determine the extent of the cancer. In an effort to preserve healthy tissue, too little tissue may be removed, resulting in recurrence of the cancer. If the surgeon is overcautious, more healthy tissue than necessary may be removed, causing excessive scarring or disfigurement.
Some tumors do not respond to common treatments, including those tumors greater than two centimeters in diameter, those in difficult locations and those complicated by previous treatment. Removing a recurrent skin cancer is more complicated because scar tissue makes it difficult to differentiate between cancerous and healthy tissue. In these cases Mohs surgery is often appropriate.
Procedure
The Mohs process includes a specific sequence of surgery and pathological investigation. Mohs surgeons examine the removed tissue for evidence of extended cancer roots. Once the visible tumor is removed, Mohs surgeons trace the paths of the tumor using two key tools:
A map of the surgical site
A microscope
Once the tumor is removed, Mohs surgeons:
Remove an additional, thin layer of tissue from the tumor site
Create a "map" or drawing of the removed tissue to be used as a guide to the precise location of any remaining cancer cells
Microscopically examine the removed tissue thoroughly to check for evidence of remaining cancer cells.
If any of the sections contain cancer cells, Mohs surgeons:
Return to the specific area of the tumor site as indicated by the map
Remove another thin layer of tissue only from the specific area within each section where cancer cells were detected
Microscopically examine the newly removed tissue for additional cancer cells.
If the microscopic analysis still shows evidence of disease, the process continues, layer-by-layer, until the cancer is completely gone.
Indication
Mohs micrographic surgery is used primarily to treat basal and sqamous cell carcinomas, but can also be used to treat less common tumors, including melanoma. Mohs surgery is indicated when:
The cancer was treated previously and recurred
Scar tissue exists in the area of the cancer
The cancer is in a difficult area where it is important to preserve healthy tissue for maximum functional and cosmetic result, such as eyelids, nose, ears, and lips
The cancer is large
The edges of the cancer cannot be clearly defined
The cancer grows rapidly or uncontrollably
Mohs micrographic surgery is performed under local anesthetic. There is some minor pain involved from the local anesthetic injections; however, once the anesthesia takes effect, you should not feel any pain. Since the process of Mohs surgery may involve several stages, the time needed for this procedure may require several hours and possibly an entire day. As with any surgery, there are possible complications and risks, such as allergic reactions, anesthetic risk, scarring, infection, bleeding, and nerve damage (both motor and sensory), among others. Final results depend a great deal on the depth of the cancer, and the amount of the nerve, muscle and other nearby tissue that needs to be removed in order to thoroughly remove the cancer. The repair will depend on the surgical defect and the techniques that are possible to give an appearance that is both acceptable to the patient, yet removes all of the cancer. Your surgeon will discuss the planned procedure with further information concerning the uncertainties and benefits of the particular tissue involved, and the type of results that you can expect. Make sure that all of your questions are answered by your surgeon during your initial consultation.
Reconstruction
The best method of managing the wound resulting from the surgery is determined after the cancer is completely removed. When the final defect is known, management is individualized to achieve the best results and to preserve functional capabilities and maximize aesthetics. The Mohs surgeon is also trained in reconstructive procedures and usually will perform the reconstructive procedure necessary to repair the wound or will work with our plastic surgeons to repair the cancer defects. A small wound may be allowed to heal on its own, or the wound may be closed with stitches, a skin graft or a flap.
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