Mohs Surgery – Conquering Skin Cancer
Mohs Surgery, named after the surgeon who originally established and evolved it in 1938, is microscopically controlled surgery used to remove cancer cells from the skin and is especially valued for its precision: it offers the unique capability of complete margin control and ensures that no unnecessary additional tissue removal, other than the cancerous cells, is performed. This is of particular value for patients who have skin cancer in anatomic areas like the face, hands, feet, nipples and genitals, where preservation of the healthy tissue is of maximum importance. It is the procedure that most successfully restricts interference with cancer-free tissue
The Accuracy of the Procedure
The standard excision of cancerous tissue usually involves cutting away 4 to 6 mm of healthy tissue around the visibly invasive cancer. Employing Mohs surgery means this is limited to 1 or 1.5 mm. The accuracy of the method is encapsulated in the acronym CCPDMA, which stands for ‘complete circumferential peripheral and deep margin assessment’. Basically, this means that examination within the surgical margin (the area containing visible cancer, which the surgeon delineates with a scalpel incision) is not merely of random samples in that area; it is a step-by-step inspection of the margin in its entirety. This ‘mapping’ or processing ensures that no residual tumour or cancerous cells go undetected.
The Convenience of the Procedure
Perhaps the two biggest conveniences are that the patient knows the results almost instantaneously and that this is a single-visit, outpatient surgery. Your dermatologist or surgeon also acts as the pathologist, the one who examines the samples of skin tissue for diagnostic clarity. Therefore, there is no delay while samples are sent elsewhere to be assessed.
There are other advantages that support its good repute. One is advised to set aside the day, yet the entire process can last as little as three or four hours. The surgeon or dermatologist will clean the area, outline the section requiring cutting, and inject a local anaesthetic. He or she removes the visible section of cancer and to ensure the deeper-lying reach of it is also removed, he will include a layer of tissue beneath and slightly larger than the tumour visible on the surface. This is done in a matter of minutes.
A temporary bandage is placed over the treatment area. The examination of each removed layer of tissue is done under a microscope, instantly, in an on-site laboratory, while the ‘mapping’ record (mentioned above) allows for no confusion or error. This does require the patient to wait in a waiting room during the initial analysis period, and any subsequently necessary one. As one need not wear a surgical gown and can read, utilize a tablet or laptop, and even eat, the delay is perfectly pleasurable.
If the surgeon/dermatologist finds any remaining cancer cells, he/she knows the exact area where they are and will remove another layer of tissue from that location until it is entirely cancer-free. Naturally, a local anaesthetic will be re-administered if additional tissue removal is required. Mohs Surgery is not only quick and painless; it also leaves the smallest scar possible.
If, however, the cancer covered a sizeable area, you might need a referral to a surgeon who specializes in reconstructive surgery. In that case, your present wound will be temporarily closed after the Mohs procedure. Normally, four alternative methods will be considered for the usual, small wound:
- Primary closure, using stitches
- A skin flap, which involves shifting skin from an adjacent area to cover the wound
- Skin grafting, which entails using skin from another part of the body (such as an invisible part of the arm, thigh, or behind the ear) to place over the wound
- Natural restoration, allowing tissue mending to occur by itself and at its own pace
There are instances when patients should consider that Mohs Surgery is not the best option for them, and in these cases, they are advised to investigate alternative methods of cancer treatment or removal:
- those suffering nervous conditions and who experience high levels of anxiety;
- those who have a surgical phobia or one about local anesthesia;
- patients whose immune systems are suppressed by medication;
- those who suffer serious diseases, such as leukemia, and
- those who are in general ill health
Consult your dermatologist for informed advice and an opinion if you feel apprehensive about being an unsuitable candidate for any part of the procedure.
However, for the vast majority of people plagued by skin cancer, Mohs Surgery is almost miraculously convenient and expedient.
The South African Society of Dermatological Surgery
Dermatology is a specialist area of medicine dealing with both the medical and surgical aspects of the skin, nails, hair and its associated diseases. The aim of our society includes providing education to our members regarding safe and effective practices within dermatology, mentoring our registrars, as well as enlightening patients in this regard with the aim of maintaining excellent standards.
For more information, visit us at www.sasds.co.za