CancerNetwork® spoke with Kay Yoon-Flannery, DO, MPH, FACS, about her experience adopting the da Vinci Single Port (SP) robotic surgical system for nipple-sparing mastectomy. Yoon-Flannery was the first breast surgeon in the US invited to train on the platform in South Korea, and following recent FDA clearance, she now performs the procedure at AtlantiCare Regional Medical Center’s Atlantic City campus, the first health system in the tri-state region to offer it for both cancer treatment and risk reduction. In this conversation, she discussed how the single-port platform’s visualization and smaller incision affect patient selection, margin status, axillary staging, and complication rates, as well as the collaboration with plastic surgery colleagues that shapes cosmetic outcomes.

Yoon-Flannery is chief of Women’s Oncology at AtlantiCare Cancer Care Institute in Egg Harbor Township, NJ.

CancerNetwork: From a technical standpoint, how does the da Vinci SP platform alter your visualization precision and range of motion compared with traditional multiport robotic or conventional open approaches?

Yoon-Flannery: I wish that we could share the 3D visualization that we’re able to do on the single-port robotic platform. It makes things much easier for us to visualize internally, and ultimately, it makes the dissection a lot more precise. I was just talking to somebody recently about what the difference is. When you do open surgery, the advantage is that it’s direct visualization, but it’s 2D visualization in a very confined amount of space; it may sometimes be difficult to get to that perfect procedure that we surgeons all want. The robotic tool gives us that clear advantage to identify the structures more clearly and to map out where you need to be in a very precise manner. I always wish that we could somehow replicate this to show the patients so that they can understand exactly why we’re so excited about this tool.

Where is the optimal incision placed when using the SP system, and how does the smaller entry point affect your access to the breast tissue?

There are differences. I’ve observed a number of surgeons internationally to develop this craft as best I could, and there were differences in technique. The majority of the surgeons I’ve observed typically tend to make an incision in the lateral axillary line, and the advantage is that it’s away from the nipple areolar complex, for instance, to hopefully maximize blood flow without any interruption created surgically. It’s also well hidden—usually under the arm—so it’s either hidden under the bra line or by the arm. If patients are looking directly at themselves in the mirror, it would be on the side and wouldn’t be directly visualized. There are other surgeons who traditionally use an inframammary incision, although that’s technically a little less optimal because of the positioning of the robotic arms. I did observe some surgeons using that inframammary incision. For the most part, though, most surgeons are using the lateral axillary line, and that’s what I prefer to do.

Does the minimized incision translate to lower rates of skin or nipple flap necrosis? What is the outlook for preserving nipple sensation?

It’s a little early to tell, particularly in the US. The early results we’re observing are that there’s perhaps some additional preservation of sensation, which has been so important for our patients. We’ve developed a separate technique that allows us to resensitize the nipple areolar complex, and I’ve been doing that with the open nipple-sparing mastectomy approach, but my hope has been that with the robotic approach, we may not need that additional procedure. Maybe the robotic approach will give us some advantage there, but it’s a little too early to tell.

The lower rates of complications, including skin or nipple areolar complex necrosis, are also an advantage that the robotic approach may provide. This comes down to technical capability, how fine a line it is to develop that perfect flap where we’re not leaving residual breast tissue behind while preserving blood flow to the skin and the nipple areolar complex. We think the robotic approach will allow us to preserve that a little better due to the improved visualization and the advantage it provides surgically.

What are some of the strict inclusion and exclusion criteria for this procedure regarding tumor size, multifocality, BMI, and proximity to the nipple areola complex?

There are some inclusion criteria: typically, a smaller tumor size, what we’d call T1 to perhaps T2—certainly fewer than 5 cm. Multifocality isn’t necessarily a contraindication or part of the exclusion criteria, but we want to preserve the cases where the tumor isn’t too proximal to the nipple areolar complex. Exactly what distance should be included remains to be seen, but a lot of us try to preserve at least 2 cm between the tumor and the nipple areolar complex. We’re also generally preserving cases where there’s some barrier between the skin and the tumor because as we’re developing the flap using the robotic approach, we want to make sure there’s some gap between the anterior flap and the tumor. About 1 cm from the skin is typically what we’re opting to include in the patient population. As for definite exclusion criteria, if a patient has a visibly abnormal nipple or nipple areolar complex from tumor involvement, they wouldn’t fit these criteria. Patients with grade 3 ptosis, meaning their nipple position is much lower compared to the inframammary fold, are also probably not good candidates. Other than that, surgeons will develop what they’re comfortable with as we expand the use of this novel technique.

How do you ensure negative margin status and perform axillary staging through this single, smaller incision?

For negative margins, we’re careful with patient selection. We don’t want to start this procedure with patients who have incredibly large tumors or tumors that are very close to the boundaries where we develop the flap. We want to be very careful to make sure the patients we select don’t have very anterior or posterior tumors. We want some gap as [often] as possible. Another way to look at this is being smart about where the tumor is located. I typically use ultrasound in the preoperative setting to mark out where the tumor is to have some understanding, as I continue the dissection, of where I’m approaching in terms of the tumor’s position. We’ll do a more careful dissection of that area. Axillary staging is possible for most patients using the same incision. Those are typically currently done under open dissection, and most surgeons do it after the tumor has been removed, so there’s a little more room to work with. With some good retraction, I haven’t had any difficulty identifying the sentinel lymph nodes with that technique.

How does your surgical strategy or patient counseling differ when performing a risk-reducing mastectomy for a BRCA carrier vs treating active disease?

Certainly, for patients who are high risk undergoing this procedure—I just consented another patient for exactly this—we don’t have to worry about axillary staging, so that part is perhaps a little easier and one fewer thing to consider. From a patient perspective, when you’re looking at this procedure from a cancer-treatment standpoint vs risk reduction, you’re coming at it from a different perspective, so I level-set with patients very honestly. Regardless of how perfect the procedure or reconstruction may be, I’m always honest with patients: the breasts will still feel different, and they’ll look different, even if we’re able to preserve the nipple areolar complex. From my patient population, most patients who’ve undergone open nipple-sparing mastectomy are generally happier than those who undergo skin-sparing mastectomy, and I do share that with patients, but I’m realistic. I tell them that even though we’re seeing early results suggesting better preserved sensation, they should expect that things will be different.

I think the expectation is certainly different when you’re looking at it from a cancer perspective. A lot of patients with cancer look at this as almost a secondary outcome: “Let me get rid of the cancer and [see] if I can preserve my nipple areolar complex sensation.” The other qualitative aspects of the surgery are great, but my ultimate goal is to treat the cancer. Level-setting the risks and benefits of the procedure and having that individualized discussion with patients about what we’re looking to achieve, what their expectations are, and what I think we’ll need to do to meet that goal is important and personalized.

Looking at the training itself, you traveled to South Korea. What do you see as the primary learning curve or milestones for other surgical oncologists looking to adopt this platform?

The number of cases that everybody looked at was very different. I asked all the breast surgeons I met on how many cases it took before they got comfortable, and it ranged. Some said it took only about 2 cases, as long as they did the formal training, as opposed to some surgeons who said even after 10 cases, they’re still developing their craft—even the surgeons who’ve been doing this for many years.

The goal of the surgery is: how can we make even the next one better than the one we just did? That’s our mantra. We always review our own outcomes after each case. I always sit down by myself to review how the case went and what I could have done differently or what other approach I could have taken. A lot of surgeons have that same logic, so there was variation, but a lot of surgeons thought about 5 to 10 cases is where you start to feel a little more confident about the whole procedure.

By offering this at a regional health system like AtlantiCare, how does keeping this advanced care local affect patient adherence and regional access?

I was so proud to be able to bring this technique to all of our patients where I live, where I treat my patients, and where my friends and family members live. It took a village, and AtlantiCare has been at the forefront of bringing not only the talent but the technology to make everything available to our patients. The breast surgeons who’ve adopted this technology in the early wave all talk to one another. We’re a tight group because we’re learning from each other’s experience and helping one another. As I was launching this program, I’ve also gotten a great number of requests, phone calls, and meeting requests from other surgeons in other areas and institutions who are interested in bringing this technology to where they are. We’re helping one another; if you don’t currently have this technology but your patients are interested, we’re talking to one another and helping them bring it on so that, ultimately, we do this together as a community of dedicated breast surgical oncologists and to bring everything available to all of our patients in our nation. It’s been a fulfilling experience but also very exciting to be able to do this.

How does this approach change your intraoperative collaboration with plastic and reconstructive surgery colleagues to maximize the cosmetic outcomes of the preserved breast envelope?

I smiled as you were asking that question because I always say the relationship between a plastic surgeon and a breast surgeon is like a marriage. You have to be in sync with one another, comfortable with each other’s techniques, and comfortable protecting one another. There’s also constant communication. The plastic surgeon I work with, Eric Chang, MD, is incredible. We’ve worked together for so many years, and he was so supportive of our decision to bring this on. I don’t think I could have asked for a better plastic surgery partner to do this together. As we do the cases, he’s right there, as he always is, doing all our cases together, wanting to make sure that the flap I’m developing is appropriate. If, for some reason, I had to go a certain way because that’s where the anatomic boundary was—if it happens to be a little closer than we’d normally like—he’s still supportive and says, “Well, it’s my job to fix it. Let me figure this out.” We pivot together, and it’s been a testament to a wonderful working relationship that we’ve had over the years.

References

AtlantiCare first in region to offer robotic nipple-sparing mastectomy using da Vinci Single Port system. News release. AtlantiCare. June 22, 2026. Accessed July 29, 2026. https://tinyurl.com/mkbn5