Alberta Cancer Foundation

Mohs is Less


TOP DOC: Dr. John P. Arlette is one of only 16 doctors in Canada who practices Mohs micrographic surgery, a process to remove cancerous moles
with minimal scarring.

“I’m just going to freeze this area, Jane.”

Dr. John P. Arlette leans over an attractive woman in her late 30s and inserts a needle in the skin surrounding a small mole on her cheek. Seated in the type of chair one usually finds in a dental office, Jane tries to relax. She didn’t expect this today; she’d just come to the Total Skin Care Centre in Calgary to get the doctor’s opinion on a new, rather innocent-looking mole. But Arlette knows that it’s basal cell carcinoma – the most common form of skin cancer – and with Jane’s family history, he has elected to include her in today’s surgical list.

Using a scalpel, Arlette expertly cuts a one-millimetre circle around Jane’s mole and lifts it away from her face. While the nurse attends to Jane, the doctor steps out of the operating room, directly into his pathology laboratory. There, he gives the tissue to his technician cuts it into sections.

Within minutes, Arlette will know if Jane still has any cancerous tissue. If she does, he’ll know exactly which tissue is cancerous and he’ll remove it, leaving only healthy tissue in place. Jane will walk out of the office cancer-free and, although she’ll have a scar, it will be as small as possible.

These are the benefits of Mohs micrographic surgery – and of being able to access Arlette, who is one of just 16 doctors in Canada practicing this technique.

Developed by Dr. Frederic Mohs more than 70 years ago, Mohs surgery is a careful, methodical way of removing cancerous tumours. Working layer by layer, physicians are able to remove the entire tumour, while leaving healthy tissue in place.

Dr. Arlette draws an analogy to an apple pie. “I take out the whole pie and I lay out the crust, which is what would be applied within the pie plate,” he says. “If pieces of apple are sticking through the crust, I would identify those as being the cancer. I go back just to that area and take out that bit.”

Using the Mohs technique, doctors remove a layer of tissue and examine it under a microscope for cancer. If necessary, the doctor can take another layer, just where cancer exists. The process is repeated until there is no cancer found in the tissue. Each time a layer is removed, the doctor is able to take out just the tissue that is affected.

Being able to take as little tissue as possible is important, agree Jane and Richard, two of Dr. Arlette’s patients whose names have been changed to maintain their privacy. Both are undergoing Mohs surgery to remove cancer on their noses.

Sidebar: The Mohs Process
Six steps to removing skin cancer tumours Read More →

“I am so nervous,” admits Jane. “Because I just don’t know how much he’s going to have to take. And I hope it isn’t too much.”

Her daughter told her it didn’t matter what she looked like afterward, as long as the cancer was gone. Jane knows what her daughter means, but she doesn’t agree. “That’s easy to say when it’s not you.”

Richard explains that he is going to have a skin graft the next day in his regular doctor’s office in Red Deer. “If necessary,” he adds. “Hopefully, they won’t have to take too much.”

Mohs surgery removes much less tissue than regular surgery, which Arlette refers to as the “best guess method.” Traditionally, the physician makes an educated guess as to the size of the tumour and then removes extra tissue, just to be sure the cancer is gone.

Obtaining a 90 per cent cure rate with this traditional method requires that the patient have five millimetres of tissue around the tumour removed. This leaves a defect at least one centimetre in diametre on the face. That can be a large amount of damage to someone’s nose or cheek.

Arlette cannot predict how much tissue has to be removed at the beginning of any one procedure. But the patient can rest assured that he will only remove exactly what is necessary, and Arlette will give just as much attention to repairing the defect as he does to the Mohs surgery itself.

“There are all kinds of things you have to be respectful of. Not only of the patient, which is so important, but also of the tissue that you’re working with,” says Arlette. “If you’ve lost part of your nose, and I have to make it up,

I have to do a good job so that you won’t think about the fact that you’ve lost part of your nose, or your ear, or your eyelid. I have to make it work well and I have to make it look good.”

In one of Arlette’s operating rooms, a nurse gives a patient the good news. “You’re clear.” The patient cheers.

“Five times a day, I get to say ‘your cancer’s gone’ and it’s rejuvenating and fulfilling for me. And for the patient, it’s so satisfying,” says Arlette. In the procedures he has completed, his success rate using the technique is greater than 99 per cent for each individual mole.

Working almost solely with cancers on the centre of the face, Arlette performs more than 1,500 Mohs surgeries each year. In total, he’s done more than 13,000. There are few physicians trained to do the procedure, largely because it requires an additional year on top of dermatology training. Arlette sees people daily from outside of Calgary who have undergone other treatments and travel here for this elite form of cancer therapy.

A training program at the University of British Columbia is the only one in Canada that teaches Mohs surgery. In an effort to train more doctors who will hopefully stay in Alberta, Arlette has worked for the last three years to get accredited and approved by the American College of Mohs Surgery to direct a Mohs fellowship program that will train one doctor annually in the procedure.

Beginning in July 2010, a physician will train alongside Arlette at the Total Skin Care Centre. The fellow will not only learn the technique, he or she will become a diagnostician to diagnose problems, an oncologist to remove cancerous tumours, a pathologist to analyze tissue samples and a reconstructive surgeon to repair the defect.

For a man who is passionate about what he does, the opportunity to pass his knowledge on is exciting. “It’s like being a father again,” Arlette says. “Within a year, someone will go from being a novice to being an expert.”


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