If you have recently been diagnosed with skin cancer, you are not alone. Over one million people are diagnosed with skin cancer in the U.S. each year, making it the most common type of cancer. Fortunately, it is also one of the most treatable forms of cancer.
Some skin cancers are readily treated with topical creams, cryotherapy (freezing), electrodesiccation and curettage (burning and scraping), or simple excision.
Mohs surgery was developed by Dr. Frederic Mohs in the 1930’s. During this procedure, the visible skin cancer is removed and processed in the Mohs laboratory, examining all of the edges of the specimen under a microscope. If any skin cancer remains, the area of remaining cancer is re-excised and, again, examined under a microscope. This process is repeated until the entire skin cancer, including any roots, is completely removed (see diagram). Once the tumor has been proven to be completely removed, most wounds are then repaired and sutured.
The Mohs technique offers several advantages over other treatments:
- provides the highest cure rate of any treatments for skin cancer-up to 99 percent
- minimizes the removal of normal skin tissue allowing for potentially smaller scars
- performed under local anesthesia as an office based procedure
Indications for Mohs Surgery:
- located on cosmetically or functionally critical areas (especially on the face)
- recurrent after failing previous treatment
- clinically ill-defined or infiltrating
- aggressive, large, or rapidly growing
Skin cancers often extend beyond their visible borders. It is these extensions that cause the tumors to recur if not completely removed.
Like other surgical procedures, Mohs surgery first removes the visible tumor.
A thin layer of normal tissue is removed, mapped and evaluated by the surgeon with a microscope.
Additional layers may then be taken precisely in the areas of remaining cancer until the tumor is completely removed.
Mohs surgery is the only method that ensures all of the tumor is removed while preserving the maximum amount of healthy tissue and therefore minimizing scars and cancer recurrence.
Frequently Asked Questions
- Located on cosmetically or functionally critical areas (especially on the face)
- Recurrent after failing previous treatment
- Poorly defined borders
- Large in size
While the majority of tumors treated by Mohs surgery are basal and squamous cell carcinomas many rare tumors such as dermatofibrosarcoma protuberans, microcystic adenexal carcinoma can be successfully treated with Mohs surgery. We also use a modified Mohs surgery on early melanoma in selected cases.
The decision for Mohs surgery verses alternative therapies is complex. Your skin specialist can assist you in the evaluation of your lesion, including biopsy, and help you decide if Mohs surgery is appropriate for you.
Upon arrival, a nurse will complete a preoperative evaluation. The doctors will clean the surgical field with an antiseptic soap and inject the area with local numbing medication. You will not be put to sleep; however, please have someone drive you home.
Once the surgical area is numb, the skin cancer will be cut out, sent to the lab and made into microscope slides. This process may take up to an hour. The Mohs surgeon then evaluates the removed tissue under a microscope. If there is some cancer left based on the microscopic exam, the process of removing tissue is repeated until the entire tumor has been completely removed based on microscopic examination.
While most patients have their skin cancers removed in two or three “rounds” of surgery, it is impossible to know exactly how many rounds it will take for your skin cancer. Expect to be here for half of a day. Similarly, it is impossible to know exactly how large your wound will be until the surgery is completed. Skin cancers can be analogous to an iceberg in their appearance in that their surface appearance may be smaller than what’s present beneath the skin.
Once the skin cancer has been removed, the wound is often sutured or repaired. The repair may be performed by suturing the skin edges together in a straight line, rearranging skin from adjacent areas (skin flap), or grafting skin removed from another site. In some instances the wound may be allowed to heal by itself without suturing. The wound size, bodily location, and even lifestyle factors determine the type of repair or healing process selected.
Common risks of the procedure include pain, bleeding, infection, scarring, numbness and nerve damage. Ice and extra strength Tylenol are the first step for pain control after surgery. The risks of bleeding and infection are approximately one to two percent, but can be minimized with careful post-operative care. While Mohs surgery guarantees the highest cure rates, no technique offers a 100% chance of a cure. There is a small chance, at least one to two percent, depending on tumor type and location, that the skin cancer will recur.
Anytime the skin is cut, a scar will develop. All steps are taken to minimize the cosmetic and functional significance of any scars. It is important to remember that complete healing of the scar takes place over a year. The surgery site may feel swollen, “lumpy”, and there may be redness for the first few months after surgery. This is part of the normal healing process.