Dr. Ashley Wysong reviews proper biopsy choice and excision techniques when melanoma is suspected.
when I asked doctor why song to come back Chairman Dermatology. Most University of Nebraska, Ashley is going to speak on melanoma, the primary lesion, the biopsy, the excision and perhaps even most surgery in selected cases. So very important topic as was your other. So welcome back Ashley, thank you so much Doctor Greenway. And I just wanted to say thank you to reverend baca as always a wonderful message for us and particularly this challenging year that we've all been living through, you know, coming from a double doctor family, I will say thank you for all of your words and inspiration And just for reminding us of the importance of the humanity and and caring for the person in front of us. And in honor of that, I'm actually going to add in a little bit of art into my talk tonight in terms of the art of medicine when uh evaluating melanoma, the primary lesion. And we're going to talk through biopsy excision and moe's surgery and select cases. Again, my disclosure is a pending research grant from castle Biosciences for squamous cell carcinoma. So just as a reminder in terms of melanoma, we are continuing to see an increase across our country. And for the first time in 2020 seer data just came out, we did surpass 100,000 cases of melanoma in the last year. So we estimated that there were 100 350 new cases of melanoma and an estimated 60 800 50 people who died of the disease which is also actually going down while the overall prevalence is going up. So a good trend in terms of mortality and what we are seeing more new cases. And as you can see here where melanoma is in the lineup. We melanoma is number five in terms of the most common cancers that we treat here in the United States. So when we're talking about melanoma the initial diagnosis is extremely important in terms of in terms of making sure that we get it done appropriately and accurately so that initial biopsy really does determine and uh that diagnosis staging work up treatment as well as prognosis for the melanoma. And so overall we tend to recommend that biopsies should be exceptional in nature and we'll go through that in more detail. So we have two major guidelines that I'm going to review in terms of biopsy of melanoma. The first is from the A. D. In terms of guidelines for the management of primary cutaneous melanoma and you can see that overall the preferred biopsy technique is a narrow excision. All biopsy, we also talk off the lot. Next line down about partial sampling or an incision will biopsy if it's a large melon aesthetic lesion and then just the whole understanding that sometimes a repeat biopsy is recommended and needed on this slide. I wanted to just review the brand new version of N. C. C. N. Guidelines that came out this month around the principles of biopsy for melanoma. And so again you can see here that the N. C. C. N. Also recommends an exceptional biopsy of some sort. And for me it really depends on the size of the lesion, the location and making sure I'm getting it all out. So if it's a smaller lesion and you can get it out with a punch biopsy which now they really come from two up to 10 millimeters in size and some even larger than that versus a saucer Ization or deeper shave biopsy or an elliptical excision. And those are the preferred biopsy techniques recommended by the N. C. C. N. Uh The N. C. C. N. Also highlighted this concept of scouting biopsies which I'm going to show you here in a little bit with a case presentation as well as the potential need for a broad shave biopsy which we often think about for a melanoma inside two or more lent indigenous type of a lesion. And so I did want to just highlight the typical technique for an exceptional biopsy And so if you are going to actually in size with a scalpel and then suit your back together. Typically we're going to want to design an ellipse that is going to be three times longer than it is wide to be able to search for that back together nicely. Oh sorry I think it's click in there 1 2nd. I'm sorry about that um versus versus what I actually like to do. And I want to bring in the art here for a reverend baca. So whenever we buy up seeing someone or performing a procedure of any type, I always love to say to my trainees, it is an honor and a privilege to be able to care for a patient and for them to entrust us with a performing a procedure on them. And so I always really make sure to take the time to position the patient appropriately. Um to do what we call Taketh asia and make sure myself for one of the staff or nurses is really talking to the patient. We do patients choice with music. We do all kinds of distraction techniques from ice to buzz therapy, tapping, tapping the patient along the side. Um Sometimes we'll use topical numbing medication if the patient is particularly concerned if it's in a more painful area. So just really even though it might be our 1,000th time performing a biopsy or a procedure on a patient, just recognizing that it's often that patients first time to undergo that experience. Um But what I wanted to show here as well in red is this is actually my preferred technique for the vast majority of pigmented lesions is I will actually take a 15 blade scalpel and score just right around the edge of the lesion here. Um with the 15 blade scalpel and then take some pickups or adsense forceps and use either a blue blade or the scalpel to actually get the depth of the lesion as well. And I find that it allows you to really excise the entire clinical lesion. Um but really not mess around with featuring or moving around potentially in the case of lymphatic if we are going to need to do a sentiment, no biopsy. So that is my technique of choice. And so this just brings up the whole concept of sampling error and sometimes the need for those scouting biopsies. So I always say if at first you don't succeed, try try again be persistent. So this was the lesion that we were very concerned about and saw in clinic um and perform one biopsy initially of the more worrisome area and it came back as melanoma inside too. And I said to our resident physicians, okay, we got to go back and do some scouting biopsies which meant we went back and sampled three or four areas to get a better idea of the over over arching um histological criteria for this lesion. And that really brings us to transected biopsies as well. And so transected biopsies or when the lesion is not removed in its entirety, Either peripherally or deep can be problematic and can potentially lead to misdiagnosis inaccurate staging uh and just overall underrepresentation of the lesion itself. There was a study that was put out in Jab that evaluated 479 primary melanomas and looked at the rate of transaction which was 1.5% for an exceptional biopsy, 4.1% for a punch biopsy in 9% for a sauce authorization or shave biopsy. And so just to give you an idea of what the typical transaction rate is for the biopsy of pigmented lesions. And the study further broke things down to try to identify areas where we might want to make sure we're thinking about death or transaction peripherally. And so shave biopsy is not surprisingly had the highest percentage of a trans section and then the locations that we see the highest level of transaction, our face, ear and digit. And these are areas where I would argue we're often trying to take a smaller biopsy or maybe you're a little bit concerned about deeper an atomic deeper anatomy in those locations. So just something to be aware of when you are biopsied. A pigmented lesion on the face here or digits. And in terms of subtypes this type that subtypes that are most commonly transacted, including the void melanomas april indigenous melanomas and nodule or melanomas. Not too surprisingly considering modular and knee void melanomas tend to have a pretty significant Breslow depth and april indigenous melanoma is I think is similar to digit where we are a little bit more cautious in our sampling technique. And this is another study that looked at the prognosis of these melanomas that are transected on biopsy looked at 714 patients of those 24% had transaction on biopsy and neither the transaction nor the lack of residual melanoma on re excision or definitive surgical excision and influence the overall survival. However, I would tend to consider these data rather cautiously as it is a rather small size and we would like to see a bigger sample size as well as longer follow up to really know what to do with that. But these are the data we have. So a little bit more information from the most recent and CCN guidelines that I wanted to go over is just that Prague gene expression profiling has been included once again and just wanted to give you guys the most recent update from the N. C C N. And so I'm going to read it to you verbatim here that the use of gene expression profiling testing according to a J C C eight melanoma stage before and after sentinel lymph node biopsy requires further prospective investigation in large contemporary data sets of un selected patients. Prognostic GP testing is used to differentiate melanomas, low versus high risk for metastasis and should not replace pathologic staging procedures more ever since there is a low probability of metastases in Stage one melanoma and a higher proportion of false positive rates with GDP. The N. C C. N. Is not recommending using GDP or gene expression profiling to guide clinical decision making in that low risk subgroup. So just an update. But I think we're seeing more and more gene expression profiling use across all the tumors, which has been discussed in several talks today. And I'm just really excited to see this technology integrated as I think it's one more piece of data once we get that biopsy to help us determine what to do next. Mhm. And so epidemiologically, I think this is really important to remember and dr blaylock put this slide up earlier, but our latest data from Seer Really highlight that melanoma is primarily a localized disease. So 84% of all melanomas that we treat are confined to the skin itself. And when melanomas are confined to the skin and have not metastasized to lymph nodes or too distant sites. The five year survival is eight is 90-98.7%. So extremely high. Overall five year survival for all of melanoma is just under 93%. But when it's localized to the skin itself, we see that the survival rate at five years is right at 99%. So very high. And so what this highlights for me is that melanoma really is primarily a surgical disease. And so I say it all the time to my residence and trainees early diagnosis and effective surgical excision is really the best therapy for melanoma. And so again, for that local disease that five year survival rate is at 99%. So if we can catch melanoma early in the localized setting if we can make sure we surgically remove it in its entirety, patients do extremely well and so that really transitions us to the surgical treatments for melanoma and I have this is a oh sorry guys my computer is trying to shut down. Okay I just stopped it. We're good. Um So melanoma really is a surgical disease and there are two major types of treatments for surgical treatments for melanoma that I like to kind of break it down and think through it a little bit more detail. So we think about surgical removal of melanoma as a single stage or as a multiple staged procedure. And then once we surgically remove the cancer it really can be processed by either frozen sections. Permanent tissue fixation or frozen sections followed by permanent tissue fixation. And so I want to go through all of that because sometimes it's really challenging when you're reviewing literature on melanoma and I think it's important to keep in mind the different surgical techniques as well as histological processing that's performed on melanoma. Because the recurrence rates do differ based on how we are surgically managing melanoma. So N. C. C. And guidelines in terms of surgical removal of the primary lesion suggest why local excision as the gold standard with removal of all tissues to the level of the fascia. They also recommend as the gold standard for histological assessment. Uh The use of permanent tissue fixation Now most micro graphic surgery is not recommended for primary treatment of invasive melanoma according to the N. C. C. N. However this is new language this year. It may be considered selectively for minimally invasive melanomas in a couple of different in a couple of different scenarios. One where standard margins cannot be achieved in anatomically constrained areas. Um And they typically will recommend doing that along with other surgical methods that provide comprehensive histological assessment such as staged excision. Which we're going to discuss with permanent tissue fixation for german dramatic pathologic review. Um And then a little bit more in the kind of weeds of the N. C. C. N. Guidelines that I haven't here in red. The N. C. C. N. Is recommending for large or poorly differentiated melanoma inside to lend to go malignant melanoma, a coral indigenous melanoma subtype or minimally invasive lent to go malignant to up to a. T. One a. Um to consider most micro graphic surgery or surgical margins with techniques for more exhaustive histological assessment of margins. And so again just as a reminder whenever we are surgically removing a melanoma. All margins are based on the clinical margins. And so just wanted to review no no major changes in terms of surgical margins with a melanoma Inside two of 20.5 to 1 centimeters uh With a Breslow depth of less than one millimeter. We're talking about a one centimeter margin removal if the melanomas Breslow depth is between 1 to 2 millimeters in depth. We're looking at 1 to 2 centimeters to remove that melanoma and then two centimeters really for anything greater than two millimeters in brazil a depth and you can see the category one evidence for these data. Okay so what do we know about the use of wide local excision and local recurrence rates for melanoma? Uh This is the largest meta analysis that we have to date. A looking at melanoma and it is broken down by trunk and extremities versus head and neck melanoma. And overall the rates of recurrence locally in the skin range from 1 to 12% for trunk and accept extremities And three as into as high as 29% on the head and neck. Where these lesions can often be lent to go malignant subtype or have more what we call subclinical extension meaning that that melanoma is just not as obvious from a clinical, from a clinical view. In addition I think it's really important to remember that there are margin discrepancies. Overall the national guidelines including the n. c. c. n. um those margins that we wreck that we just discussed were extrapolated from studies primarily of invasive melanomas ranging 1-4 mm in depth and traditionally these studies did exclude melanomas on the head and neck as well as the distal extremities. So we're gonna kind of keep that in mind. There is some data in the literature that does suggest a couple of things for melanoma and site versus invasive melanoma and a lot of this work is done by broad line and to tell the out of Pittsburgh looking at M. I. S. There is a suggestion that sometimes margins as high as 12 to 15% 12 to 15 millimeters are needed to remove the majority of head and neck melanomas. And you can see here that that nine millimeter margin is required to remove a 99% of melanoma insight is based on a review of their data. And when you're looking at invasive melanoma, sometimes that sometimes we think potentially the mark that potentially smaller margins may be needed. Um In looking at these data, 97% of the invasive melanomas that they treat and they treat all brussels deaths are removed with a 1.2 centimeter margin. So just to say that not all melanomas are the same and each individual melanoma could need a smaller or a larger margin in order to completely remove the tumor. And then I did. I just also just want to bring up this whole concept of patient protoplasm and that what a patient's underlying immuno suppression, um whether or not there is a lot of background sun damage. There are lots of things that can actually affect local recurrence or nodal metastasis. When we think about local recurrence. I think it's sometimes important to think through whether or not this is his persistent tremor meaning inefficient excision of that primary lesion or potentially whether there was perry neural invasion extensively or neuro trope is um that may have been missed on pathologic removal. Um And overall if we are thinking about how to optimize local control melanomas and I believe would benefit from complete margin assessment and more exhaustive margin assessment. If we're thinking about the best way to improve local control. Now in terms of nodal and distant metastases if it's not present on initial presentation. Um there are really really two different ways that a tumor can then go on to metastasize. One is if there's still persistent tumor or a. Ca and insufficient excision and there's tumor left behind. That tumor obviously can go on to metastasize versus really if the cat's already out of the bag there's nothing no on nodal staging whether it's clinically or pathologically but that but there's still some circulating tumour or tumour and lymphatic sort that's just on its way or in transition. That obviously is something that we can't control. But those are those are things to consider as well when surgically removing that primary lesion and then finally tumor biology that's an aspect that we really don't have a great handle on. But we're starting to learn a lot more in melanoma and other cutaneous tumors is extremely important for predicting metastases and um potential recurrence. Okay so we talked a little bit about wide local excision which is a single stage procedure and primarily using permanent tissue fixation to surgically remove melanoma. And it is considered the gold standard by N. C. C. N. Guidelines. Now because of those higher rates of local recurrence that we've talked about particularly head, neck melanomas but even on trunk and extremities, melanomas. And in the context of what we've discussed about the importance of really getting that surgical that melanoma lesion out first and the best chance for cure is that first time around a multiple different centers and physicians and groups over time have come up with staged surgical excision techniques to really get at more comprehensive margin assessment and better local control for melanomas. I'm going to kind of just discussed several different staged excision techniques. The first is the square technique that was put out by the University of michigan and was initially published in the jacket in 1997. And what this involved, as you can see here is taking initially either five or 10 millimeter margins and creating a square around the actual melanoma. Uh The the the tissue is then processed by on fox or vertical sections to make sure all the melanoma is out. Um If there is a positive margin anywhere along the peripheral area, additional layers are taken until the peripheral margin is cleared and then the melanoma is excised in its entirety and that central square is removed down to fascia And the lesion is closed. This this initial paper looked at 35 cases and had zero recurrences. The second major technique I want to discuss is the map serial excision and what this removed. What this involves is initially starting a five millimeter or 10 millimeter clinic are surgical margin. Um The lesion is surgically removed and then it is inked with four different colors of ink all the way around across the four corners. And there are an increased number of pathologic sections that are taken and after a paraffin embedded and they are cut at 122 millimeter intervals. And overall the five year recurrence extrapolated rate of 136 cases in this publication was 5%. So again, just trying to get at techniques to sample a larger percentage of the margin with the goal of to hire a local control of melanoma. This is the perimeter technique which is very similar to the square technique only. It's kind of rounded around the actual lesion itself. And typically a five millimeter margin is taken with a to strip two millimeter strip of skin around that uh and the section orientation is unclear or how many sections they recommend doing. But the goal is to remove and get the periphery clear and then come and surgically remove the center so very similar to the square technique. And then finally, a radio section in which you may come across as well is where you surgically remove the tumor. And then when you remove the actual the actual skin peripheral margin, it is actually sectioned radio lee to increase the overall sampling of that peripheral margin. And again with the goal of sampling and assessing a larger percentage of the peripheral margin of the melanoma. And so a comparison of all of these techniques that was put out in this in this paper and overall, Oh sorry I think it's going forward again. Overall you can see that the wide local excision. Again we said rates can be up to as high as 12% for um Trunk and extremities, melanomas and as high as 29% for head and neck melanomas. Uh from for most surgery With the square tech. I'm sorry for surgical excision with the square technique as and staged um stage techniques. We were just talking about a recurrence rates are really ranging in the literature from 0% up to five or 6%. Okay. And so we've kind of alluded to the whole concept that it's important to completely remove melanoma on initial excision. And this is the paper that just shows you the numbers on this. So of melanoma inside to that does surgically come that does come back locally in the skin. That happens 23% of the time. And when that melanoma site Inside two comes comes back it has an invasive component with an average depth of .9 mm Of invasive melanomas that are surgically removed and come back a 33%. Have a deeper Breslow depth with an average Breslow depth increase from 1.53 to 2.83 in this paper. So just again highlighting the importance of really surgically removing in its entirety on the first go. Okay so finally I would like to move into stage techniques that we call most surgery. And I'm going to give you a little bit more about the different terminology because I think it can be a somewhat confusing. So most micro graphic surgery is a surgical technique that is that is used to exercise in this case melanoma and to perform an exhaustive margin assessment to remove that cancer overall. We it is touted to have high local curates as well as can be can improve tissue conservation. Although I will say in melanoma we're not typically worried about this as much. And just as a high level overview this is just a concept of how uh pathologic assessment is different between standard uh standard pathologic assessment or bread loafing versus most sections. So on the left here you can see if you did a typical wide local excision in an ellipse. And I always like to think about that is that if it were a loaf of bread. And so for standard wide local excision and vertical sectioning. What you would do is kind of slice that bread, take out a couple samples or pieces of the bread. Look at the crust on those sampled or specific pieces of bread and make an assessment about the overall margin. And it's really important to note that the N. C. C. N. Guidelines as well as local recurrence rates are based on uh these margins. And so while there is a smaller percentage of the margin sample typically we think anywhere from 1% to 20% of the complete margin is sampled. Um It is important to note that the the the margins are based on this and so we know that these margins work for the vast majority of melanomas. But I think what the reason where complete margin assessment comes in is for those melanomas where it is not they are not captured or completely removed on initial surgical excision. So with most micro graphic surgery and what happens is that three D. Piece of tissue is removed and it's processed while it's fresh or not fixed by formalin and embedded. Um And so while it's fresh it's a little bit more pliable. And you can take that three D. Piece of tissue and relax it down into two D. And you can process it in a way that you can see all the way around the edges and all the way underneath. To do a complete assessment of the margins and so location, location, location. I think it's important to kind of think through where are the tumors located. And this is extremely important when you're thinking about the type of surgical excision that might be most beneficial for any given patient. Uh And so when you look at the trunk and extremities that this is a study that came out in 2016, um you can see high cure rates of 97 to 98% were seen if the margin was nine millimeters for trunk and extremities, 12 millimeters for hands and feet and up to 15 millimeters necessary on the head and neck. So just again showing us that certain locations in certain subtypes may may need additional margin. Okay, so a little bit of terminology. So most surgery is named after Frederick mose and we typically think about that as a complete margin assessment. Histological processing for most surgery can be by the fresh tissue technique or can be done by permanent tissue fixation or what we tend to call in our field slo moes or modified mose. Um And then histological staging are staining can be H. And E only or H. And E. With multiple different immuno stains, including martin. One Hmb 45 S. 100. And in our lab we're now using socks as well as prime. All right, so we're thinking about doing surgery of any kind. This is a little sidebar pearl of mine. I always use a wood's lamp when doing clinical marking of a lesion. And this is a perfect case that shows the importance of using wood's lamp which can highlight the the actual pigment that's within the skin that may not be as obvious to the naked eye. So on the left here you see a typical picture, The biopsy was right here in the center. Um but when I turned the wood's lamp on, I could see that there was a significant amount of pigment pigment. Well beyond what my I could see. Well, despite that, I was like, oh man, no way can the melanoma be that large? And so I went ahead and it was a melanoma inside to mark out the five millimeter margins, but did do a couple scouting biopsies, these smaller circles below and lo and behold they were melanoma inside too as well. And so we did have to come back for a second stage. But just that clinical um Pearl, that the wood's lamp can be very helpful for identifying the clinical lesion itself. And I think this is extremely important that we identify the boundaries of the clinical lesion to the best of our ability, because we then want to take our surgical margin beyond that clinical lesion. Yeah, okay. And I did just want to discuss the concept of surgical de bulk. And we'll go through that technique. And so the surgical debug because essentially is essentially removing that clinical lesion with a little bit of a surgical margin. I typically take 1 to 2 millimeters around that clinical lesion and we will uh surgically remove it in its entirety and send that off for exhaustive vertical section to ensure that there's not a deeper melanoma present and the reason this is important. And it's shown by this meta analysis put out by Don at all in 2 2000 and seven a nearly 25% of lesions initially diagnosis M. I. S. Were subsequently found to have an invasive component a lot when they were surgically removed in entirety. So just important to remove that clinical lesion to do some exhaustive sectioning throughout it. Okay. And this is a great diagram from the pen group that shows the technique for surgical de bulk. And so again they're kind of marking out a couple of millimeters around that clinical lesion uh and removing that and sending it off for exhaustive vertical sectioning and then taking the complete surgical margin and down to fashion for invasive melanoma. Um Now with most surgery, you're going to then go ahead and take the remaining surgical margin and then, as we talked about, process it in a way that we can see all the way around and all the way underneath. It is inked and processed by the most surgeon and then either sent off for permanent tissue fixation. Put informal in and then embedded in paraffin or it is processed by the fresh tissue technique utilizing O. C. T. And the most surgery lab. Every most group is a little bit different in terms of the initial clinical surgical margin that is taken. But you can see the ranges that are typically published in the literature of 3 to 5 millimeters for an M. I. S. Or 3 to 10 millimeters for an invasive melanoma. And with processing for permanent tissue fixation. Again, you can see it here. I'm going into the cassette after it's gone informal in and then it is embedded in the paraffin versus the O. C. T. Here on the right for most surgery. And so what do we know about recurrence after Moe's surgery for melanoma utilizing H. E. staining only? Um the very first paper came out in 1997 by snow and dermatologic surgery and looked at 179 cases. Um and that was the first time it had really been published. The next paper was looking at that slow most permanent tissue Fixation technique at Michigan and showed a recurrence rate of 1.4% at five years, 1.8% at 7.5 years and 2.2% at 10 years. And then this hotel group put out a paper in 1997 showing a local recurrence rate of .5% utilizing fresh tissue technique and h. and s staining. Now, the new kid on the block over the last several years has been the introduction of immuno staining into the most surgery. Um Both the fresh tissue technique as well as permanent tissue technique and again these are the major stains that are utilized and as dr henderson mentioned earlier today, a premium is increasingly being utilized in milan acidic lesions and one other just kind of surgical technique thing I wanted to highlight is the majority of most surgeons particularly if they're doing fresh tissue technique will also take a small biopsy whether it's a little punch or a shape of a sun damaged lesion as well as normal skin particularly when we're dealing with head and neck melanoma led to go malignant subtype superficial spreading on a patient with significant background and actinic damage. And this can be really helpful. And so the really do want to highlight. And this is even called out in the N. C. C. N. Guidelines with respect to disease related outcomes. There have been no prospective comparisons of different surgical excision methods including wide local excision. Most micro graphic surgery and staged excision with permanent tissue fixation. And so all randomized controlled trials. Every section margins for invasive cutaneous melanomas were performed using standard wide local excision technique. And but it is really important to know. And the N. C. C. N. Guidelines do call out very few of these prospective randomized controlled trials involved head and neck melanomas or april indigenous melanoma. So we want to kind of keep keep that in mind. However we do now have some new data that is retrospective in nature of comparison and comparing in this case outcomes of melanoma insight to treated with most micro graphic surgery compared to wide local excision rates and you can see the five 10 and 15% 15 year recurrence rates for melanoma inside too. And that is local recurrence rates and they are significantly lower in most surgery compared to wide local excision uh in the five and 10 year. Um And not the 15 year Now. The other study is looking at the benefit of most surgery over wide local excision for melanoma of the head and neck. So looking specifically at the head and neck location. And as you can see here looking across um the wide local excision versus most micro graphic surgery. And again this is a retrospective study done by Peter lee's group Uh and there is a statistically significant difference for all tumors for insight to tumors and uh for invasive tumors less than .8 mm in depth. And so just kind of something to keep in mind in terms of the data that we do have. So what what do I typically do and what would I recommend based on the N. C. C. N. Guidelines Based on what we what the data that we currently have for primary surgical treatment of melanoma I do believe. And I am biased as a mohs surgeon that there are several areas where we should consider most micro graphic surgery or a complete exhaustive surgical margin technique. And in the cases where I think that that's important are lent to go malignant subtype because they have quite a bit of subclinical extension melanoma in situ or thin T. One a melanomas on the head and neck. A melancholic melanomas which in my experience have significant subclinical extension and we can leave a lot of you're behind if we're not using complete margin assessment. A coral indigenous melanoma. I am humbled on a daily basis by this disease. I think it has a lot of subclinical extension. I often have to go multiple most layers to surgically remove that that type of melanoma in its entirety. And then based on N. C. C. N. Guidelines when standard margins cannot be obtained based on an atomic constraints. So a lot of times we'll see like a melanoma right here on the cheek where you can't get the full one centimeter or two centimeters around that lesion. Uh the N. C. C. N. Recommends considering most surgery or some other type of complete margin assessment. And then finally I just want to bring up. There is while there's significant literature describing the use of most for deeper melanomas. It's absolutely more controversial. Uh thick melanomas those greater than 0.8 millimeters. In conjunction with sentiment no biopsy we are doing that in my in my institution specifically for high cosmetically sensitive areas. Let's go malignant melanomas and april indigenous melanomas. And we do that in conjunction with our surgical oncologist and in conjunction with our head neck oncologist for the really high risk lesions will often go into the O. R. And do the surgical reception alongside of the surgical oncologist will take the tumor. And then they'll move forward with the sentinel lymph node biopsy. So we do quite a bit of that. This is one case that I just want to highlight april indigenous melanoma here on the heel of this patient. I perform the reception in the operating room. You can see that the blue dye for the sentinel lymph node biopsy had already been placed at that point uh surgically resected it, processed it, inked it and did send it off for permanent tissue fixation. Uh and the patient had a significant amount of melanoma still remaining. I would say 90% of the periphery was still involved. So he is now, as you can see here in my clinic for stage two to surgically remove it And guess what? He was still positive about 60% of the periphery. So this is him coming back for stage three. Uh And he he's particularly complicated kind of circling coming back full circle to the very beginning of the talk. He's an april melanoma. And he was transected by an outside physician for the initial biopsy. And so we actually never did know his final Breslow death because he was transected at 1.1 millimeters. And we did not see any additional depth of melanoma on his multiple re excisions. And so he went underwent same day sent a lymph node biopsy. Um And so sometimes we do just need to think creatively and outside of the bag to take exceptional care of each individual each individual patient. I don't think there's a one size fits all for for any given patient but we absolutely follow N. C. C. N. Guidelines and then think creatively when we need to for some of those locations specific to us and to do the right thing for our patients. Okay so final couple slides. So we've surgically removed our melanoma. We've done the best we can to get it out in its entirety with depending on the sub type of tumor, the location of the tumor the patient, protoplasm. All these things were taking into account. And so now what? Uh so I just wanted to briefly go through the N. C. C. N. Guidelines for follow up. Uh and so stage one A two stage two a melanoma said the N. C. C. N. Is recommending that there is a full H. And P. And skin check every 6 to 12 months for five years then annually as indicated afterward routine blood tests are not recommended. Routine imaging to screen is not recommended uh And unless there are symptoms or other things of concern. So just to keep in mind and I just did want to highlight that we are starting to see moving into melanoma and multiple other types of cutaneous and other tumors that gene expression profiling and in addition to helping us inappropriate to us to identify those that may go on to metastasize or may benefit from sentinel lymph node biopsy. We are also starting to see tumor biology playing a role in helping us with surveillance and follow up as well. And so this again is just highlighting when we're talking about deeper melanomas that the duration and frequency of follow up and intensity of cross sectional imaging should be based really upon that likelihood of recurrence in those areas. Okay, so final take home points. I think super important. Remember melanoma first and foremost is primarily a surgical disease. Again, 84% of all melanomas are localized to the skin alone. And if we get it out right, we're doing a great job already. We have a very high curate uh five year survival rate of just over 98%. But I think we can really identify those key locations where we might be able to do um might be able to get the highest rate of local control and select cases. All right. And this was our last skin cancer screening. Obviously pre covid but prevention is the very best way. So surgical excision is important once we've gotten the melanoma. But prevention and early detection is just essential to what we do. So, thank you again. Dr Greenway for having me for this session. Dr barrett as well for the entire melanoma conference and happy to answer any questions that people might have. As we move into the break