Surgical Management of Locoregional Melanoma

Transcript:Jeffrey Weber, MD, PhD: Hello, and thank you for joining us today for this OncLive Peer Exchange® panel discussion on “Global Perspective on Management of Malignant Melanoma.” Along with the extensive progress we’ve experienced in the field of melanoma research comes increased complexity surrounding the optimal use of available tools for treating patients with advanced disease. The goal of this OncLive Peer Exchange® discussion with a panel of international experts is to provide clarity and perspective on the latest clinical data, and practical advice on how new information applies to the clinic.

I’m Dr. Jeffrey Weber, and I’m the deputy director at the Laura and Isaac Perlmutter Cancer Center and professor of Medicine at the NYU Langone Medical Center in New York. Participating today on our distinguished panel are: Dr. Reinhard Dummer who is vice chairman for the Department of Dermatology and head of the Skin Cancer Unit at the University of Zurich Hospital in Switzerland. We have Dr. Axel Hauschild, professor of dermatology in the Department of Dermatology at the University of Kiel in Germany. Dr. Caroline Robert, professor of dermatology and head of the Dermatology Unit at the Gustave Roussy in Paris, France. And, finally, Dr. Dirk Schadendorf, director and chair of the Department of Dermatology and director of the Comprehensive Cancer Center at the University Hospital Essen in Essen, Germany. Thank you so much for joining us. Let’s begin.

Let’s talk about the treatment of local regional melanoma. So, Caroline, when you see a patient in the clinic who has advanced disease but is probably surgically resectable, how do you approach it? That is, how do you decide on resectability?

Caroline Robert, MD, PhD: Well, we always discuss it in a multidisciplinary meeting with the surgeon, and if the patient is resectable, of course, he or she will undergo surgery. The question is, what is going to happen afterwards? Because we know that depending of the number of nodes that are involved, the fact that it’s microscopic or macroscopic disease, the recovery lapse will be more or less important. And, until now, it was very difficult because besides clinical trials, we didn’t have really any treatment that was really effective with a good risk—benefit ratio to decrease the risk of relapse.

Jeffrey Weber, MD, PhD: But that, then, brings up the question of, in a day and age when we have effective adjuvant therapy, how aggressive should you be in sampling the lymph nodes? Dirk, do you always do a sentinel lymph node biopsy? And, if it’s positive, do you always advise that the patient have a completion lymphadenectomy? So, that’s a controversial issue. How do you handle this?

Dirk Schadendorf, MD: I think sentinel node biopsy is the best prognostic procedure we can do, at the moment, to find out about the prognosis of our patients. So, that’s a mandatory procedure. Indeed, we are finding roughly, depending on the tumor thickness, in up to 25% of the patients, that there is some minimal tumor load in the lymph node. The question is, should elective complete lymph node dissection be performed? The current guidelines, at the moment, most of the guidelines across the globe, are recommending this. There is some upcoming discussion, now, whether this is always mandatory. Whether this, also, is possibly related to the tumor load in the lymph node. I think we have to wait for the next scientific results, particularly the study initiated by Don Morton, the MSLT-II study results, which hopefully will give a definite answer on that.

Jeffrey Weber, MD, PhD: Yeah, it’s funny, at least in my institution it seems like the practice precedes the data. So, for example, a number of surgeons at my institution will decline to do a completion lymphadenectomy if the sentinel node shows microscopic disease. Reinhard, what do you tell a patient who has, perhaps, a thin melanoma, maybe 1-mm-thick with no ulceration, and then has a microscopically positive sentinel node? Do you always tell them to have a completion lymphadenectomy?

Reinhard Dummer, MD: Actually, this is a very important question and I have to tell you, no. This was still important because in the classification, even single tumor cells are counted as a positive sentinel node. Some years ago we had done complete lymph node dissection based on this, and we know, now, that this is wrong, because these patients’ behaviors concerning their prognosis is very similar with these patients who do not have a sentinel node. So, the node is the most important thing. Based on the published data in Lancet Oncology earlier this year, we really have to restrict the indications. These data that are out there suggest the minimal tumor load of approximately 1 millimeter. Everything that is below 1 millimeter should, in my personal opinion, not undergo complete sentinel lymph node dissection.

Dirk Schadendorf, MD: We have got a lot of scientific evidence that actually measures the tumor load and the sentinel lymph node, whether it’s more than 1-mm in diameter, or less than 1-mm, so we have 3 different categories. A group from Rotterdam, Amsterdam, and Berlin proposed this classification. It’s very helpful in finding the category of prognosis for these patients, and also guiding us in our recommendations. The German guidelines, which have been released over the summer this year, have actually taken that up already, and in patients with more than 1 millimeter, there is a stronger recommendation in doing this.

Jeffrey Weber, MD, PhD: To do the sentinel lymph node.

Dirk Schadendorf, MD: Yes.

Jeffrey Weber, MD, PhD: So, Axel, if you had a patient with microscopic disease less than 1-mm, and you advised them not to have the completion lymphadenectomy, how do you follow them, both systemically and in the nodal basin? What do you do?

Axel Hauschild, MD: Let me give one comment to Dirk’s German guideline remark. Because I think it’s important to say that, in Germany, you need to discuss the issue of the controversy of the complete lymphadenectomy in sentinel node—positive patients with the patient if the tumor load and the sentinel node is below 1-mm—that’s important. You need to discuss it. Whether the patient is saying yes or no to your recommendation is another issue, but you need to discuss it. That’s very clear, and also, surgeons need to do it because there might be a conflict of interest.

But, on the other hand, I think it’s very important that patients who are refusing the advice for complete lymphadenectomy, and there’s patients even with more than 1-mm diameter, the sentinel node, who are not taking the completion of lymphadenectomy, that in these patients you need to have good follow-up evaluations according to the German guideline. I think, internationally, it’s more or less the same. It’s a 3-month follow-up for these patients.

And, we, in Germany, as in some other European countries, are always using lymph node sonography, which is the most sensitive and specific tool for investigating the sentinel node. Even if you have very sensitive finger tips, you know, you’re not as good as the lymph node ultrasound. And, therefore, you know this is mandatory in these patients. You can pick up the patients with a relapse in the lymph node basin then, certainly, it’s a case if the patient is willing to undergo a complete lymphadenectomy.

And, the vast majority of patients, in Germany, are patients who have low tumor load in the sentinel node because the tumor load corresponds to the tumor thickness of the primary tumor. And since a median diameter of the tumor, in Germany, the vertical tumor, tumor thickness, is relatively low compared particularly to Eastern Europe. It’s not many patients who have a high thickness primary tumor, and, therefore, most of the patients have low tumor load in the sentinel node.

Jeffrey Weber, MD, PhD: So, the irony is that, over time, over the last 20 years, it appears as if we’ve been doing better on surveillance and we’ve been detecting the tumors earlier.

Caroline Robert, MD, PhD: I would like to also insist on something. You have to rely on your pathologist. It’s important that you work with a pathology team that you know. And, not all the pathologists would be familiar with looking at a sentinel node. So, that’s something very important because we rely a lot on them. So, you have to make sure.

Jeffrey Weber, MD, PhD: And, will you follow these people with any scans, or will you just sonogram the basin?

Caroline Robert, MD, PhD: We would also do clinical follow-up and sonogram every 3 months. And, we would do some CT scans.

Axel Hauschild, MD: We are doing the same. I was not saying it because I was thinking about the patients who have not received a completion lymphadenectomy. But, all patients in stage III receive 6 months and CT scans.

Dirk Schadendorf, MD: For 2 years.

Jeffrey Weber, MD, PhD: For 2 years? And, then, what will you do after 2 years?

Axel Hauschild, MD: That’s the question. For most of the patients, I like to have more scanning. And, if we are scanning, we are using MRI, particularly if it’s a young patient because we are afraid of the radiation load. In most of the patients, we stop.

Transcript Edited for Clarity