Edmonton Dermatology | Mohs Micrographic Surgery
Hi there. Welcome to the Edmonton Dermatology YouTube channel. My name is Trevor, and I’m here with none other than Dr. Muba Taher. He is the main dermatologist here and skin surgeon at Edmonton Dermatology and Skin Surgery Center. And today our topic is going to be Mohs micrographic surgery. Now, here’s a quick quote for you from Alma Aiden: Skincare is so much more important than makeup. Makeup is for when you’re having fun and going out, but your skin is forever. And here’s a fun statistic from Forefront Dermatology: The skin renews itself every 28 days. Now, Dr. Taher, what is Mohs surgery?
So, Mohs micrographic surgery is a very specialized kind of surgery that’s utilized to remove certain types of skin cancers, and it does so in a very special way so as to minimize the amount of skin that’s removed, while at the same time it gives the best chance of successfully removing every bit of that cancer root, which equals a complete cure to your skin cancer.
Excellent. So what does Mohs stand for?
Most people think the word Mohs is an acronym for something, whereas in fact Mohs refers to the physician who pioneered the entire technique. In fact, it was Dr. Frederic Mohs in the United States several decades ago who came up with this technique—a rather clever technique that allows us to remove the cancer in such an efficient way.
Excellent. Now, how long has Mohs surgery been around for?
The earliest forms of Mohs micrographic surgery have been around for decades. I would say at least since the 1950s and 1960s. The current form of Mohs micrographic surgery is a little more sophisticated than its original form, but it’s a technique that’s been around for many decades now.
Excellent. So, Dr. Taher, what types of skin cancers does Mohs surgery treat?
The two most common skin cancers that are treated with Mohs micrographic surgery are basal and squamous cell carcinomas. One reason is simply they’re the most common types of skin cancers, and they lend themselves to this technique as an efficient cure. However, there are several other rare cancers that can also be treated using this technique.
Okay. Now, can you explain to me how this surgery is performed?
There are a number of steps, and just to summarize it, basically what happens in Mohs micrographic surgery is the cancer is removed using local anesthetic. The cancer is cut out. After the cancer is cut out, it is immediately sent into a specialized lab, which processes the tissue using a specialized technique, and slides are created within half an hour to perhaps a couple of hours.
Again, it depends on the cancer, the size of the tissue, and so on. This is very different from other techniques where you have to wait days, if not more than a week, to get your result. So the tissue is sent while you are waiting, and the cancer is then analyzed under a microscope. The surgeon—myself—would study it under the microscope looking for any evidence of cancer roots remaining.
Now, in the meantime, we’ve removed the cancer. The patient is left with a wound. We do not reconstruct the wound at this time because we want to be absolutely sure all the roots are gone before we commit to reconstructive surgery. So typically dressings are put on, the patient is waiting in a specialized waiting room, and once we get the results, we update the patient. That’s when we decide: Do we need to cut more, or is this the time to start thinking about possible reconstructive surgery?
Wow. That sounds like quite the intensive process. Now, do people have to be put to sleep in order to do Mohs surgery?
No. This is a procedure that’s generally done under a local anesthetic. So no, we don’t put you to sleep, and this is one of its benefits. We can use local anesthetic; you’re wide awake. I’m talking to my patients, calming them down, getting to know them. The cancer is removed, they’re dressed, and because there’s waiting involved, we wouldn’t want to keep a patient under a general anesthetic for that long. So it’s a technique that’s done under a local anesthetic.
Okay. Now, does Mohs surgery hurt a lot? Or what kind of pain is associated with this type of surgery?
At the time of the procedure, local anesthetic is initially infiltrated into the skin, which means that the patient has to endure at least some initial poking, and there can be a little sting from the anesthetic. There are several tricks to minimizing that initial sting from the local anesthetic, and that’s where my expert nurses and I use every trick we can to make it as minimal an initial discomfort as possible. Once the anesthetic goes in—and it works fairly quickly—within minutes of the anesthetic being placed, we can go ahead and start our procedure.
So, Dr. Taher, can you tell me how you know if there are any roots of the skin cancer left in the skin?
The way we cut the tissue and the way we process the tissue lends itself to allowing for a 100% assessment of the root margins.
I’ll explain it this way: The cancers that are treated with Mohs surgery have a pattern of growth where they start at the top and they move down. This has to be the case; otherwise, this technique wouldn’t work. So if a cancer starts at the top of the skin and moves down, which is the way these cancers behave, if you cut from underneath the cancer and you look at 100% of the bottom margin and see absolutely no cancer, that means you’ve gotten deep enough and wide enough to have the cancer removed.
Think of it as uprooting a tree or a weed, for that matter, in your lawn. If you go wide enough and you pull up that weed with some soil and you look underneath the weed and you don’t see any roots piercing the margin of the soil that you’ve uplifted, you know you’ve got the cancer contained—or in this case, the weed roots contained—within the bunch of soil that you’ve pulled out. In a similar fashion, when I cut the cancer out, I look at 100% of the peripheral and deep margin. If I do not see any cancer roots, that confirms that the cancer has been completely excised.
Wow. That’s excellent. So how long does the typical Mohs surgery take?
A typical layer that’s taken may have a turnaround time of anywhere from one to two hours. Again, it depends on the size of the tumor. If it’s a bigger piece, it may take longer as far as tissue processing and studying it under a microscope. So what we tell our patients, just to standardize, is usually one to two hours between the time that I excise your cancer, it’s processed, I study the margins, and I update you. So between one to two hours later we will have a result for you. Generally speaking, sometimes it’s a little bit faster, sometimes a little bit longer.
Okay. Now, at that point, can someone say that they are cured of skin cancer after the Mohs surgery?
Yes. The Mohs micrographic surgery procedure provides the best cure rates for these types of cancers. And so when we can confidently say that all the roots are cleared, you are cured of your skin cancer. Again, as I mentioned earlier, there are specific cancers that we would use this technique for.
Okay. Now the next question I have for you, Dr. Taher, is what happens to the skin after the skin cancer’s been cut out?
When the cancer is removed, you’re left with a portion of your skin missing. Now, it’s obviously a bit of the upper layer, and depending on how deep the cancer goes, there will be deeper layers that are removed. So you’re left with some degree of a wound. Depending on how deep that wound is, sometimes we may recommend that we just let this heal in by itself, and that’s sometimes the smart way to go.
Whereas at other times, for best results—depending on the size, the depth of the wound, and the comfort of the patient—we may recommend some type of reconstruction to fix the wound. That’s part of our skill set: to provide local reconstructive surgery on the skin. Some techniques that may be used include skin grafting and local flaps. There are different ways to fix a hole that’s created after cancer removal.
Okay. Now how long does it take to heal from Mohs surgery in most cases?
In most cases, especially if the wound is sutured and reconstructed, stitches typically come out somewhere in the range of seven to 12 days, depending on which part of the body. The stitches come out, and then usually there’s another week or two after that where you just have to give your body a little extra time to allow for the final bit of healing to occur and for things to seal up and the scar to mature.
Great. So the next question that I have for you, Dr. Taher, is what are the contraindications to Mohs surgery?
I would avoid Mohs surgery if I was assessing a cancer, for example, that was of a certain significant size. Again, because it’s under local anesthetic, if it was, let’s just say, a significant portion of the face or ear, I would be concerned that the amount of local anesthetic I would need to operate on that case might go beyond what we consider a safe level.
So when we see cancers that are significantly sized, it’s sometimes better to have our hospital-based surgical colleagues involved. Sometimes for those cases, we need to do certain special radiology testing to make sure the cancer hasn’t spread deeper or to a distant site. That would be an example of where I may say Mohs micrographic surgery is not right for you.
There are certain cancers that don’t grow in what we call a contiguous fashion—from the top down. If they are more scattered and random and grow in a disorganized fashion, the technique will not work, because we need to tackle cancers that grow in a contiguous fashion from the top of the skin downward.
Another reason I wouldn’t recommend micrographic surgery is if the patient, when I meet with them and tell them about the technique, is extremely anxious and very honest with me, saying that they don’t think they can handle a series of repeated local injections. It just may not be right for them. I’ve had patients who realize their cancer is very small and that micrographic surgery might be the better option; however, they may choose to have it cut under a general anesthetic just because they can’t handle the anxiety of micrographic surgery.
Dr. Taher, are there some patients that you wouldn’t do Mohs surgery on?
Although micrographic surgery is an excellent option for certain skin cancers, there are situations where I wouldn’t recommend it or I would use other techniques. For example, if a patient had several other illnesses or medications that would make them a higher bleeding risk and they absolutely can’t stop those; or if they had other medical problems that would make it difficult for them to tolerate a potentially long day of surgery, I would look to other options as more suitable for those cancers.
Excellent. Now the last question that I have for you: If someone thinks they might have a skin cancer, how do they get booked in for Mohs surgery?
The first thing you should do is talk to your family doctor. They are a great first resource to look at the spot that you’re concerned about and to give you further advice as to whether they’re concerned. Perhaps it’s actually something minor that they can reassure you about. If they have any concerns, that’s when they would make referrals for further assessment at a surgical center such as ours.
We would meet with you, assess the growth that you’re concerned about, and possibly do an initial biopsy just to confirm our impressions if we were worried about a skin cancer. Sometimes our colleagues take care of the biopsies for us. For example, I have colleagues who are excellent dermatologists, but they don’t do the procedure that I do, and so they may do your initial biopsy and assessment, and if they think micrographic surgery is the preferred option, they would get me involved to further look after your skin cancer. Similarly, your family doctor may wish to do the biopsy, and once they get the result, they may have me involved in your care.
Thank you so much, Dr. Taher, for sharing all that information about Mohs micrographic skin surgery. We hope that you were paying attention during that video and keep in mind any changes that you might see in your skin. If you are concerned, see your family doctor and they can refer you to a qualified skin surgeon and dermatologist like Dr. Muba Taher. And thank you so much for joining us here, and we have more videos to come. We appreciate you looking at our channel. If you like what you see here, give us a thumbs up and please share it across YouTube.