Clipping of Lymph Nodes May Aid Axillary Surgery in Breast Cancer

In clinically node-positive breast cancer, clipping of lymph nodes may induce higher rates of sentinel lymph node surgery after neoadjuvant chemotherapy.

The utilization of clipping and localizing a biopsy-proven positive lymph node may lead to less invasive axillary surgery, with comparable false-negative rates, according to study results presented at the American Society of Breast Surgeons 25th Annual Meeting.

In a retrospective analysis of the phase 2 ISPY-2 trial (NCT01042379), patients underwent sentinel lymph node (SLN) surgery only, SLN and axillary dissection (ALND), or ALND only following neoadjuvant chemotherapy. Investigators found that patients with clipped nodes are more likely to undergo SLN surgery only, compared with ALND (75.1% vs 31.2%, respectively; P <.001). Further, those who underwent both procedures and had clipped or non-clipped lymph nodes demonstrated similar false-negative rates (12.8% vs 9.4%, respectively).

In an interview with CancerNetwork®, Roshni Rao, MD, FACS, chief of the Breast Surgery Program at NewYork-Presbyterian/Columbia University Irving Medical Center, discussed the role of clipping the lymph node of patients with node-positive breast cancer who underwent neoadjuvant chemotherapy.

CancerNetwork: What are the main factors that might explain the increase in clipping biopsy-proven positive lymph nodes?

Rao: The whole concept is that someone comes in with lymph node metastases, and you want to try to downstage the axilla. You want to be able to give them chemotherapy or endocrine therapy, get the cancer out of that lymph node, and then you don’t have to do an axillary lymph node dissection, you can de-escalate [therapy] and do what people are calling a targeted dissection. To do the targeted axillary dissection, you have to have a clip placed in that lymph node at the time of the biopsy, then [the patient] gets the therapy. Then you find that same node again, and you see if it has cancer in it or not.

It’s a very well-thought-out concept, if that node had cancer. You go back and look at that node again, after the treatments, and see what the response is. As far as why the rates are increasing, the ACOSOG Z1071 (Alliance; NCT00881361) trial came out and proved that this was an effective way to find that node, and that the false-negative rate was quite reasonable. Even with doing sentinel node [biopsy], 80% of the time that clip node is a sentinel node, which is also good. [Clinicians] have adopted the trial results, which was rapid, because people felt that there is a clinical need for that, then subsequently, more and more people have become comfortable [with it], particularly the radiologists.

This goes to the multidisciplinary [approach]. I remember when this whole concept first started, they’re only doing fine needle aspirations of the nodes because it’s an area with a lot of blood vessels and it’s difficult, and we might have a lot of bleeding and it might be uncomfortable. Then the radiologist became more familiar with clipping the node and taking a good core. It’s just a natural evolution of that, that now the radiologists are very comfortable placing clips, doing big core biopsies of the lymph nodes. I think it’s great.

Are there any advantages or disadvantages to specific localization techniques, or is the choice mainly based on surgeon preference?

The ISPY-2 study came out, what we wanted to do with this study was to figure out what clips were placed or what localization was placed to figure out which one was optimal, but we just don’t have that data within that database. That wasn’t part of the original plan for ISPY. I think that should be the next iteration of what is the best way to clip that node and find that node. Magseed is great. A lot of places are more familiar and more comfortable with wires. We do Savi Scout [so my institution], it is whatever your team is most familiar with. Since there are technical issues with biopsy in your lymph node, putting that clip in the right spot, that’s part of it as well. There’s always this concern, let’s say you have a big lymph node, and you put a clip in it, you put it in what you think is the middle, but then the patient has a response, and then all of a sudden, the lymph node shrinks significantly, and then that clip is not sitting in the lymph node anymore. How do you find that? They’re all those types of technical issues that had to be worked out. There are still some concerns, but I think most of the time, we’re able to find that now.

Is there any further research or anything warranted that investigators should investigate further?

We do need to figure out what is the best clip that you place at the time of the first biopsy. Ideally, you should be able to place a clip that can be in there the whole time, prominently, and will work when it comes time for the surgery. Then the question becomes, what if that lymph node is negative? Then you didn’t need to put that fancy clip in there, because you could have just done a sentinel node biopsy without that. Those are the questions that I think need further clarification to figure out the best techniques. Do you put a clip in there that you could see on an ultrasound? Even if there’s a clip in there, it’s not something that can’t just stay in there or doesn’t have any other consequences. That’s where we need to go.

Is there anything we didn’t touch upon that you think our breast surgery audience should know?

The biggest thing is, if I can just speak from a patient perspective, many times I have patients who want to know, is it safe to have the clip? Can we leave it in there? … The clip is important. Even if you’re the medical oncologist, occasionally the patients will get to the medical oncologist for their initial workup rather than the surgeon. That clip is important for us to know about before treatment is started. It’s also important that when that clip is placed, that clip is removed because my radiation oncology colleagues are very nervous when that clip is still in there. That brings up the question of whether should we place a clip in a negative node.

Reference

Switalla K, Boughey J, Dimitroff K, et al. The Role of clipping the lymph node in clinically node-positive patients treated with neoadjuvant chemotherapy for breast cancer: impact on axillary surgery in the ISPY-2 clinical trial. Presented at: The American Society of Breast Surgeons 25th Annual Meeting; April 10-14, 2024; Orlando, Florida. Abstract 1678051.