Moh’s Micrographic & Skin Cancer Surgery

Mohs surgery is a highly effective treatment for certain types of skin cancer. It is an exacting procedure in which the dermatologist performs both surgical excision of the skin cancer and microscopic examination of the surgical margins to ensure that all skin cancer cells have been removed.

Some skin cancers can be deceptively large – far more extensive under the skin than they appear to be from the surface. These cancers may have “roots” in the skin, or along blood vessels, nerves, or cartilage. Skin cancers that have recurred following previous treatment may send out extensions deep under the scar tissue that has formed at the site. Mohs surgery is specifically designed to remove these cancers by tracking and removing these cancerous “roots.”

For this reason, prior to Mohs surgery it is impossible to predict precisely how much skin will have to be removed. The final surgical defect could be only slightly larger than the initial skin cancer, but occasionally the removal of the deep “roots” of a skin cancer results in a sizeable defect. The patient should bear in mind, however, that Mohs surgery removes only the cancerous tissue, while the normal tissue is spared.

The Mohs Surgical Procedure 

The dermatologic surgeon begins the procedure by marking out the tumor site. The procedure is performed under local anaesthetic. The dermatologic surgeon removes the visible cancer, along with a thin layer of additional tissue. The excised specimen is prepared and processed by a histology technician, tissue is then carefully examined by the doctor and any areas of residual cancer identified are marked on a map. The patient returns to the operating room where the process is repeated. The process can be repeated as many times and necessary to ensure complete removal of the cancerous tumor. Once the tumor has been completely excised the dermatologic surgeon can begin the repair and closure of the surgical wound.