Who Knows Mohs? Mohs Surgery in the Treatment of Skin Cancer
Non-melanoma skin cancers, particularly basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), are by far the most common types of skin cancers. There are about 900,000 cases per year of BCC, and over 200,000 cases per year of SCC in the United States. Although genetic factors are involved in persons being predisposed to these skin cancers, the evidence is overwhelming that excessive sun exposure is the most likely cause.
Mohs surgery or Mohs micrographic surgery (MMS) is a surgical technique for the removal of BCC and SCC with high risk of recurrence. It involves taking special horizontal sections of skin tissue and examining them under a microscope. It differs from other surgical excision techniques which normally involve examination of vertical sections. The technique was first developed by Dr Frederic E Mohs in the 1930s and has been refined and perfected over the last 50 years, although the unique process of examining horizontal tissue sections, color coding excised specimens and creating a map to identify location of remaining cancer cells to be excised remains the cornerstone of the procedure.
The cure rate for MMS is very high (up to 99%), although other treatment modalities give cure rates almost as high as MMS. Electrodessication and curettage, radiation therapy, and wide surgical excision are other treatment options for BCC and SCC with cure rates in the 92-95% range. Patients may opt for these more conservative methods for treating skin cancer if they are on blood thinners, are poor surgical candidates, or simply do not wish to undergo a time-consuming and complicated surgical procedure that may require closure with a skin flap or graft.
Although the wide majority of BCC and SCC are clearly-defined tumors in low-risk sites, some of these cancers may form with undefined edges and lengthy rootlike extensions that can grow deeply or laterally from the clinically visible lesion. In these cases, Mohs Surgery is particularly suitable because it is able to identify and remove all cancer tissue including that found in finger-like extensions. This allows higher cure rates and less scarring.
Standard indications for Mohs Surgery being the treatment of choice for skin cancer are the following:
- Recurrent or incompletely excised BCC and SCC
- Primary BCC and SCC where the edges of the cancer cannot be clearly defined
- BCC and SCC in an area where it is important to preserve healthy tissue for maximum functional and cosmetic result, such as eyelids, nose, ears, lips, and genitals
- BCC and SCC that is large (> 2cm in diameter) or growing rapidly
- Cancer arising in scars or in sites of previous radiation therapy
- High risk or aggressive types of SCC (e.g. infiltrative histology, poorly differentiated)
The American Academy of Dermatology recommends that each person get a complete skin evaluation on a yearly basis with a dermatologist. Dermatologic skin exams are still considered the gold standard method for detecting skin cancers. Feel free to contact as at www.heckerderm.com or by phone at 954-783-2323 for an appointment for Mohs surgery.