publication date: Apr. 5, 2019

Conversation with The Cancer Letter

MSK’s Kirstein: Robotic mastectomy not demonstrated to be safe for treatment or prevention of breast cancer

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Laurie J. Kirstein

Breast surgical oncologist,

Memorial Sloan Kettering Cancer Center

 

The Breast Surgical Service at Memorial Sloan Kettering Cancer Center has decided not to adopt—or study—robotic surgical devices in mastectomies, said Laurie Kirstein, a breast surgical oncologist at MSK.

“We discussed it as a group under the leadership of our chief of breast surgery, Dr. Monica Morrow, fairly recently in the last few months, to assess the procedure from an oncologic perspective,” Kirstein said. “There have been no studies whatsoever to show if it’s oncologically equivalent, or not inferior, to what we already do in terms of recurrence and whether that recurrence risk impacts overall survival.

“And so, it’s very hard to adopt a new procedure that hasn’t been really tested, when the one we have is so good, and we know is safe.”

On Feb. 28, FDA issued a safety advisory, indicating that device manufacturers looking to market surgical tools for use in the prevention or treatment of cancer may now be required to study long-term oncologic endpoints in surgical trials “for time periods much longer than 30 days” (The Cancer Letter, March 1).

“At this point, given the recent FDA statement on robotic surgery and since the safety of the procedure has not been demonstrated, it’s not something we are pursuing at Memorial Sloan Kettering,” Kirstein said.

 

Kirstein spoke with Matthew Ong, a reporter with The Cancer Letter.

 

Matthew Ong:

Thank you for discussing this with me. I became aware of robotic mastectomies after Dr. Stephen Chagares started doing it at Monmouth Medical Center and widely advertised the procedure. When did MSK start thinking about robotic mastectomies?

Laurie Kirstein:

We don’t do them currently. We do not believe the safety of this procedure for cancer treatment has been demonstrated and do not think it should be performed outside of an IRB approved protocol with appropriate informed consent.

So, we discussed it as a group under the leadership of our chief of breast surgery, Dr. Monica Morrow, fairly recently in the last few months, to assess the procedure from an oncologic perspective. But that was only fairly recently, as the technique has also become a little bit more popular in the United States, without, so far, any data showing that it’s oncologically safe.

 

MO:

How did your team arrive at the decision to not perform the procedure at MSK?

LK:

The only studies that have been done for the robotic mastectomy have been on cosmesis and patient satisfaction and length of stay and things like that.

There have been no studies whatsoever to show if it’s oncologically equivalent, or not inferior, to what we already do in terms of recurrence and whether that recurrence risk impacts overall survival.

And so, it’s very hard to adopt a new procedure that hasn’t been really tested, when the one we have is so good, and we know is safe.

As a group, we discussed it, and the question of whether any of us were interested in learning how to do robotics—potentially come up with an IRB or come up with some sort of clinical trial, in which we could test the technique in a more rigorous, oncologic way—was brought up amongst the group.

At this point, given the recent FDA statement on robotic surgery and since the safety of the procedure has not been demonstrated, it’s not something we are pursuing at Memorial Sloan Kettering.

The issue for us is that you have a procedure that is going to be much longer than your standard mastectomy. It’s a lot more expensive than your standard mastectomy, and we’re not really sure that it’s cosmetically better in the long run than what we already do for, let’s say, a nipple-sparing mastectomy or other ways to do it.

 

MO:

Can you explain in greater detail why it’s not cosmetically better and why current standard of care is, as you said, so good that there is no immediate reason to move to robotic techniques?

LK:

What we have today is, let’s say that a patient wants to have a nipple-sparing mastectomy, which is what the robotic offers—we do them now with incisions that are incredible well-placed, so that they are either in the inframammary fold or somewhere that heals that you don’t see it.

Even though the incisions are a little larger than what they do with the robotic mastectomy, you can see much better, you have much more better visualization so that you can see the tissue planes that you need to dissect in order to make sure that you are really getting out all the breast tissue—with the technique that’s current.

You really want to make sure you get out all the breast tissue. You want to make sure you can see all the way around when you are doing a dissection, and you want to take it out in one piece, or en bloc.

And the concern for the robotic mastectomy is that the first part of the dissection is actually done blindly. There is no visualization, and the robot is only really used for the far-medial, or the piece that is closest to the chest bone. So, there’s a concern about being able to see what you’re doing and making sure you’re actually getting out enough tissue.

There were concerns for other surgeons, where they took out the tissue in pieces, rather than in one en bloc section—so it’s very hard or impossible to evaluate margins, for example, for a cancer, if you haven’t taken it out in one piece. You’ve sort of chopped it up into pieces. And so, oncologically, we know that’s not the right way to treat patients.

So, for now, we have these great techniques to be able to hide our incisions and so, and it’s a quick, much faster procedure. It’s much less expensive, so patients in the long run look great.

It’s easy to do a mastectomy and leave a lot of breast tissue behind and really look good, because then it’s nice and soft, and it’s supple. But that’s not a good cancer procedure.

So, unless you can see what you are doing, and you can make sure that you’re really doing everything that you’re supposed to, it’s not safe for the patient.

 

MO:

What’s the risk profile of patients coming in for breast surgery, generally? I understand that even patients who choose prophylactic mastectomies because of atypia or BRCA mutations are high-risk.

LK:

Correct.

 

MO:

Are any of these patients low-risk?

LK:

So, those are not low-risk patients. The patients who are at average risk for breast cancer are those who are, obviously not high-risk—so, patients who don’t carry BRCA mutations, patients who haven’t been diagnosed with a TPR lobular carcinoma in-situ.

The concern about robotic mastectomies on that population—those patients are screened regularly, at much more regular intervals than the average population; right?

So, we see these patients a couple of times of year. Sometimes they are screened with MRIs in addition to mammograms. If they were to have an inadequate robotic mastectomy, they would no longer be getting screened, because they would be told that they had a mastectomy, and therefore the tissue that was left behind, which is usually a fair amount in robotic mastectomies, is at much higher risk for developing breast cancer. And then they’re not being screened. So, that’s of concern.

 

MO:

What are the chances of finding an incidental or preoperatively undetected cancer at the time of prophylactic mastectomy for women?

LK:

In the BRCA population, it’s about 10 percent of the time there’s some incidental cancer that’s found; nine out of 10 times that’s ductal carcinoma in-situ.

When you look at the average-risk patients, it’s usually even lower than that. Once in a while, you’ll see patients who had a reduction mammoplasty, like a breast reduction, and they will have a DCIS.

If they had a negative mammogram beforehand, and they will incidentally, have a DCIS, and that doesn’t happen very often, but it does happen.

 

MO:

So, is robotic mastectomy appropriate for any population in women?

LK:

No, we haven’t been able to prove that yet. We’ve not been able to prove that at all. We haven’t been able to prove that it’s a procedure that can be done that’s adequate compared to the ones that we already have.

 

MO:

And that includes fragmentation or leaving tissue behind?

LK:

It follows that, right.

 

MO:

Lumpectomies leave breast tissue behind as well, but that is done with good margins. This might be rhetorical: what’s the difference here?

LK:

The difference is that, after a lumpectomy, patients routinely receive radiation treatments to the remaining breast tissue.

Multiple randomized clinical trials have demonstrated that this controls any undetected cancer that might be left behind. Radiation is not routine after a mastectomy. In addition, women having a lumpectomy are followed with breast imaging including mammograms.

When you have a mastectomy, robotic or otherwise, there’s no imaging that’s being done to screen. If there’s tissue left behind, nobody’s screening that tissue for cancer.

 

MO:

I see. So, is there a problem with framing these robotic procedures that we’re talking about as “mastectomies”?

LK:

You could say that. Yes.

 

MO:

Because when you call something a mastectomy—and for good reason—you are promising the patient that you’re removing the entire breast to lower or eliminate the risk for recurrence of disease, or tissue with malignant potential being left behind?

LK:

Correct.

 

MO:

But, with robotic “mastectomies,” you’re saying that there is no certainty of that, as we know it?

LK:

Correct.

 

MO:

In your review of existing literature, including European and Italian studies on this matter, do these studies take into consideration cancer-related outcomes or cancer risk as primary endpoints?

LK:

They haven’t. Zero. There are no studies doing that. The only study that has been published so far was an Italian study, in which they reported patient-reported outcomes such as patient satisfaction, length of stay and cosmetic outcome. That’s it. There were no volumetric studies; there were no cancer-related studies. Nothing.

 

MO:

But, for at-risk populations—which includes all women, it seems—shouldn’t cancer-related outcomes be the primary focus?

LK:

Yes, if you think about it as akin to the other surgical specialties, which have adopted robotic procedures, such as gynecologic oncology and colorectal surgery, they did side-by-side evaluations of robotics vs. standard open procedures, or laparoscopic procedures, and they did a rigorous study with thousands of patients, with long-term follow up. Both of those studies have shown that it is not the best procedure in terms of risk-recurrence, for different populations.

Just recently, the study out of MD Anderson on robotic hysterectomies for cancer was published, suggesting poorer outcome with the robotic surgery.

 

MO:

The two practice-changing papers that were published in NEJM in October.

LK:

Right. And there were similar issues with colorectal surgery. None of those studies have been undertaken in breast cancer and robotic surgery, and that is concerning.

 

MO:

Are we looking at parallel scenarios here in minimally invasive surgery? In gynecology—for instance, power morcellation for presumed benign hysterectomies and myomectomies, and you mentioned minimally invasive radical hysterectomies for cervical cancer—these procedures were adopted as the standard of care before prospective data testing cancer-related outcomes had been generated.

LK:

Right. That’s what we’re concerned about.

 

MO:

Was MSK worried that this might happen in breast surgery as well, that if your department did not look at this in a prospective way, this might have evolved into a new standard of care without Level I safety data?

LK:

That is correct. We all want that Level I data before adopting new procedures or drug therapies especially for cancer patients, right?

When you are going to change what you do drastically, you really should have Level I data showing that it’s at least not inferior to what you’re doing.

That being said, we have no current plans to study this at MSK, and, given the recent FDA statement, don’t consider it a priority.

 

MO:

And when you say “drastically,” you mean this is not just a tweak to the standard of care? What do you call this?

LK:

This is a major change, a major deviation. A major change in the standard of care and in the technique.

 

MO:

So, the main takeaway is that there is no apparent or real advantage of robotic mastectomies over existing standard of care, as far as MSK is concerned?

LK:

Correct.

Copyright (c) 2019 The Cancer Letter Inc.