Overview
Mohs surgery is the most precise technique available for removal of skin cancers and has the highest cure rate (98-99%). It is especially suited to treating BCC’s on the face where it is critical to remove the minimum amount of tissue and ensure no tumour is left behind. Essentially, it is a technique that allows the surgeon to test the edges of the excision on the day of the surgery while you wait. It allows the surgeon to remove only a very narrow margin of normal skin around the tumour and to remove further skin if the edges are found to be not clear of tumour. Mohs micrographic surgery was named after its inventor, Dr Frederick Mohs. A Mohs surgeon requires many years of medical and specialised training and as such there is currently a great shortage of Mohs surgeons in Australia.
The technique
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 only1-2 mm larger than the clinical tumor. Next, this tissue is processed in a unique manner and examined under the microscope. On the microscopic slides the doctor examines the entire bottom surface and out-side edges of the tissue. (This differs from the frozen sections prepared in a hospital setting which, in fact, represent only a tiny sampling of the tumor mar-gins.) 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.
Once the tumour is completely removed, your Mohs surgeon with repair the defect, using the most suitable plastic surgical technique to give the best chance of an excellent cosmetic outcome.
Visit the website of the American College of Mohs Surgery for an information video of the procedure: http://www.mohscollege.com/
