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News release on NanoKnife for prostate cancer gets nano-score

New Data Establishes Image Guided Treatment Option for Prostate Cancer as an Alternative to Surgery by Reducing Recovery Times and Lower Side Effects

Our Review Summary

physician and patientThere is much interest in the treatment world about the area of irreversible electroporation (IRE), which is a new way to damage cancer cells inside solid tumors, including prostate cancer tumors, by using an electric current. IRE, marketed as the NanoKnife, is a “new minimally invasive surgical technique that selectively kills tumor cells by using electrical fields to make holes in cell membranes,” according to Stony Brook School of Medicine which has begun using the method to treat certain types of pancreatic cancer. As exciting as the topic may be, this news release drops the ball on several levels. The Germany-based study claims to show that results from 265 patients showed fewer side effects with an image-guided IRE therapy for their prostate cancer than they would have had with other methods. But the claim is never backed up. Cost, valid evidence, alternatives and context are all missing from the release — hence the 1-star score.

Note: We’ve previously reviewed a different news release about the NanoKnife and covered the fascinating dispute that ensued between University of Louisville employees over the source of that news. 


Why This Matters

Estimates put prostate cancer as the fifth-highest expenditure of all cancers in the United States, with a yearly cost of about $10 billion in 2010. Any treatment that would lower costs (such as hospitalization and surgery) and decrease side effects, such as impotence and incontinence, would make an enormous difference. This news release missed its chance to educate the public and practitioners in two ways: by promoting ahead of peer-review publication and by failing to include some context about the size of cost burden.


Does the news release adequately discuss the costs of the intervention?

Not Satisfactory

The release does not discuss costs.

Does the news release adequately quantify the benefits of the treatment/test/product/procedure?

Not Satisfactory

The release does give a list of outcomes, and uses quantitative language to describe them, but there’s nothing to substantiate the claim that these outcomes are better than what would be achieved with a more conventional treatment approach. The release doesn’t mention outcomes like survival time that are obviously of critical importance to patients. And because this research has not been published in a peer-reviewed journal, the data cannot be judged as credible and acceptable by typical professional standards. The release does not tell us anything about the study protocol. It does state it was “an analysis of clinical data” so it wasn’t a controlled trial. Randomized and controlled trials are needed to achieve high standards in research.

Does the news release adequately explain/quantify the harms of the intervention?

Not Satisfactory

The release makes several different claims about the superiority of this treatment method to others — but never brings up the potential of harm.

“The patients we have treated in the Prostata Center have had their cancers destroyed without the need for surgery, with a low incidence of side effects and in most cases have been back on their feet the next day,” the release states. [Italics ours].

The word “destroyed” is not typically used in medicine. Even if there is a “low incidence” of side effects, we would like to know what those rare side effects are.

Further, the news release provides no information about how side effects were measured (e.g., standardized measures completed by patients, physician assessments–which is not considered reliable), how many men actually completed reports of complications, the median length of follow-up–saying “up to  4 years” is very imprecise. (They could have been followed just 6 months, 1 year, and so on.)  Another problem is that the recurrence group included men who had already been treated with surgery or radiation–which do cause erectile dysfunction and urinary incontinence. To interpret complication data the reader needs to know the level of urinary control and sexual function before the IRE treatment. The release also does not describe how recurrence was defined, whether all men were evaluated, and–again–the median length of follow up.

Does the news release seem to grasp the quality of the evidence?

Not Satisfactory

The release describes a study with data from 265 patients, and includes some details about their stage of cancer and their results in a follow-up of up to 4 years. But the release does not describe how the study was conducted which weakens the credibility of the data provided.

While we know the study was not randomized and controlled, we then looked for credible evidence about benefits.  A big problem with the study is that T3 and T4 tumors (and the report does not indicate how many of the tumors were in these categories) have spread beyond the prostate and are not curable. This makes it very difficult to understand what the authors meant by “tumor control” and “recurrence.”

Does the news release commit disease-mongering?


The release does not use disease mongering language.

Does the news release identify funding sources & disclose conflicts of interest?

Not Satisfactory

The release did not identify funding sources for the research. Frehling is the director of a for-profit treatment center, Prostata.

Does the news release compare the new approach with existing alternatives?

Not Satisfactory

We would have liked to see the release outline the typical alternatives for a patient presenting with prostate cancer, and explain how this image-guided IRE therapy compares to other therapies.

The release states: “Unlike other treatment procedures for prostate cancer therapy, image guided or IRE only destroys cells; vital tissue structures are not affected.” But it doesn’t outline side-by-side the alternatives for patients.

Currently, cryotherapy or other local therapies are not recommended as therapy for primary or recurrent prostate cancer due to lack of long-term data comparing these treatments with radiation and surgery, according to the National Comprehensive Cancer Network (NCCN). For patients with recurrent cancer, the typical treatments include hormone therapy, chemotherapy, immunotherapy, and radiopharmaceutical therapy.  Treatment choice for recurrent cancer would depend upon the initial stage and whether “recurrence” meant biochemical progression (PSA increase) or clinical evidence of progressive or metastatic cancer.

In this release, the group studied was not described well enough to know which alternative therapies would have been appropriate.

A common problem with early-stage primary cancers is overtreatment.  An appropriate option for many men with low-risk cancers is “active surveillance” — not receiving any active treatment because there is no evidence for benefit.  We do not know how many of the study subjects had low-risk cancers.

Does the news release establish the availability of the treatment/test/product/procedure?

Not Satisfactory

When a release is all about a “new” therapy, it is important to establish whether this technology and expertise is available only in academic centers or more widely in the community or hardly at all and only in clinical research. This release does not tell us anything about when and where this might be made available. If the investigator is just now reporting up to 4 years of data on only 265 subjects then this is not widely available.

Does the news release establish the true novelty of the approach?

Not Satisfactory

The release does not provide context about the use of IRE for prostate or other cancers. Readers could easily come away from this release thinking that this is the first time outcomes have been reported on the use of IRE for prostate cancer. But other researchers have been looking into this. Also, IRE has a longer track record of use in pancreatic cancer that wasn’t mentioned.

Does the news release include unjustifiable, sensational language, including in the quotes of researchers?

Not Satisfactory

There are a few sentences in this release that we can’t confirm and sound unjustifiable. Here are two examples, with our comments in italics.

“Dr. Stehling has treated the most prostate cancer patients in the world using this image-guided treatment.”

We would have preferred the number of patients he has treated, rather than “most in the world.”

“Data found that the most common side effects are either eliminated or greatly reduced using image-guided treatment.”

We believe you can’t claim both “eliminated” and “reduced” at the same time. It is one or the other.

Total Score: 1 of 10 Satisfactory

Comments (6)

Please note, comments are no longer published through this website. All previously made comments are still archived and available for viewing through select posts.

Jonathan Cohen

December 9, 2015 at 9:26 pm

Just as an FYI, Stony Brook School of Medicine began using IRE in late 2009 for certain types of pancreatic cancer, and stopped mid 2014 with the departure of Dr. Kevin Watkins, who was the IRE practitioner at Stony Brook. To say “has begun using the [IRE] method” is misleading. Interested persons might consider Dr. Watkins’s study published in September 2015 in the ANNALS OF SURGERY, titled “Treatment of 200 Locally Advanced (Stage III) Pancreatic Adenocarcinoma Patients with Irreversible Electroporation: Safety and Efficacy.” Based on their data, he and his co-authors conclude: “For patients with LAPC [locally advanced pancreatic cancer] (stage III), the addition of IRE to conventional chemotherapy and radiation therapy results in substantially prolonged survival compared with historical controls. These results suggest that ablative control of the primary tumor may prolong survival.” Yes, _res ipsa loquitur_.


Erich Zuri

December 22, 2015 at 1:52 pm

If you delete comments as listed above you should have never posted the review by the three persons listed.

I was diagnosed to have prostate cancer in September of 2014. My PSA score was at 8.4 and my Gleason score at 7A (after a anal biopsy which nearly killed me)!

After reviewing my options which included surgery, radiation or the brachytherapy I was referred by my doctor to Dr. Stehling, located in Offenbach, a town near Frankfurt! My urologist was totally against the relative unknown method and suggested for me to only consider the three option earlier mentioned.

In May of 2015 I underwent an MRI at the institute
In July of 2015 a 3D biopsy was done and confirmed the finding of having prostate cancer.

On September 17 I underwent the IE nanoknife procedure. I spent one night in hospital to monitor my catheter which caused some pain. On September 18 I went to Munich (my temporary home) and on September 26 I took some clients to the Oktoberfest. On September 29 I went back to work.
Two weeks after the IE procedure my PSA went to 4.8 and my current PSA is at 0.1 (December 7)!
All other functions are back to normal as before!

The cost was less than US$ 15K which my US insurance paid!

If you want more proof I can forward all my medical records…….


    Gary Schwitzer

    December 22, 2015 at 3:34 pm

    Mr. Zuri,

    I’m not sure you grasp the purpose of our project.

    We review media messages about health care and we apply standardized criteria to do so. We ‘ve done this on more than 2,300 news stories and news releases.

    That’s what our 3 reviewers did in this case – 3 reviewers who represent decades in health care journalism and in the practice of medicine; the physician-reviewer specializes in shared decision making on prostate cancer issues.

    On the other hand, you left a comment on our site that reflects on your personal experience – an anecdote of one. We’re pleased for you that you’re happy with your choice.

    But, from an evidence-based perspective that is an N of 1. And our reviews don’t deal with Ns of 1. And we don’t give medical advice.

    We’ve posted your comment, even though it misses the mark on the purpose of our site. So you need not send us all of your medical records. It wouldn’t make a difference with what we wrote in reviewing the news release in question. We know that the NanoKnife will help some people. You may have been one of them.

    The point of our project is this: in this example, the news release made claims and didn’t back them up with evidence. We don’t view that as an acceptable practice. It doesn’t say anything about your choice or your outcome or your satisfaction. It’s a comment only on the quality of the news release. Period.

    We didn’t malign any procedure nor the people who deliver it. We didn’t question anyone’s choice and we don’t need proof of anyone’s experience. We’ve set a standard for media messages and this news release message didn’t meet that standard.

    Gary Schwitzer


      Erich Zuri

      December 26, 2015 at 10:13 am

      Gary, tell me. What is the purpose of your review on The NanoKnife IRE procedure ? That is well written liken an assay? That a price tag is attached? Or is it to inform readers that the IRE is a choice when dealing with Prostate cancer?

      Before I underwent the IRE procedure I contacted several patients who were cured by Dr. Stehlings procedure!

      Anyway, my review (as a patient) it 10 out of 10……….

      Gary Schwitzer

      December 26, 2015 at 12:05 pm

      Mr. Zuri,

      I’ll try one more time to make this clear and if it’s still not clear to you this time, let’s end this thread because it is becoming repetitive.

      We did not “review the NanoKnife IRE procedure” per se as you state. We reviewed a news release that included claims about the procedure.

      We don’t review medical procedures. But we do review media messages – including news releases – that include claims about medical and health care procedures. Period. That’s what we do. We apply 10 standardized criteria to such reviews.

      So your patient perspective about the procedure – “10 out of 10” – is great for you. But we don’t review individual patient anecdotes.

      We reviewed a news release that didn’t meet our standard – failing on most of our criteria. You can disagree with our criteria if you wish. But this is what we do.

      Our purpose, in reviewing media messages, is to help these media do a more accurate, balanced, and complete job in reporting about claims about interventions. But it’s also to help consumers hone their critical analysis of such claims. Again, period. That’s what we do.

      Please don’t translate what we clearly do into something that we clearly don’t do. We don’t give medical advice.

      Gary Schwitzer