… Are we getting things out of proportion?
The CyberKnife® system was initially developed as a method to treat tumors in places like the brain that were inaccessible to physical surgery, and was originally approved by the FDA in 1992. Now it is being touted as “the next thing” in “radiosurgery” for prostate cancer.
In 2003 an article was published by King et al. that reviewed the theoretical potential of the CyberKnife in treatment of prostate cancer. And a Phase II clinical trial has been initiated to explore whether CyberKnife surgery really does have potential in the treatment of prostate cancer. The trial hopes to enroll nearly 300 patients and won’t report outcomes until some time in 2014. This is the sort of thing that can happen when large number of people start to present with a treatable condition: the numbers and types of treatment start to expand, sometimes exponentially.
Of course, because the CyberKnife is already approved, there is nothing to stop CyberKnife users from carrying out such “radiosurgery” today. And some centers clearly are. If you want to get an idea of the marketing that is already in place, have a look at this link (just as an example). This morning in my mail I received an invitation to an “eSymposium” on CyberKnife use in the treatment of prostate cancer, in which one of the speakers is an employee of the manufacturer of the CyberKnife technology.
Here are some questions that need better answers than those offered below:
- Is CyberKnife as effective and as safe as other forms of therapy for the treatment of localized prostate cancer? Answer: We don’t know.
- What is the cost of CyberKnife treatment for localized prostate cancer? Answer: We don’t know, but the equipment alone costs around $4 million.
- Is the average health insurance carrier reimbursing for CyberKnife treatment of prostate cancer? And what about Medicare? Answer: We don’t know, but it would surprise us if they are.
- Would you have considered CyberKnife therapy for prostate cancer, if it had been available when you were treated? Please let us know by posting your comments below.
Please let us be completely clear. CyberKnife therapy may be an absolutely wonderful form of treatment for localized prostate cancer. But what we know at the moment is that:
- Many men who get actively treated for localized disease may not need treatment at all (especially some of the older ones).
- Most men who have treatment for early stage disease do well with available therapies.
- The available data on the short-term (let alone the long-term) outcomes of CyberKnife therapy for prostate cancer are minimal at best.
- There are only three papers on CyberKnife therapy for prostate cancer in the PubMed database (and not one of the three offers peer-reviewed clinical data).
- Several centers are actively promoting this form of therapy, despite the limited outcomes data available.
Finally, so that we are not accused of being out of date curmudgeons (or similar), you may want to read one patient’s view of the situation. We offer the following link to Donn Rosenauer’s decision to go with CyberKnife therapy.
Filed under: Management, Treatment | Tagged: cancer, CyberKnife, localized, prostate, radiosurgery, robotic
Search for new and
ongoing trials on the
CTAG PCa web site
Cyberknife is a radiotherapy device, like many others, that can be used to treat many different conditions. There is nothing Cyberknife-specific about treating some prostate cases with only a few (i.e. five) radiation fractions using a technique called “stereotactic hypofractionation”. “Stereotactic” meaning that the treatment is extremely precisely delivered and “hypofractionated” meaning that the treatment is given in fewer than standard treatment sessions.
Prostate cancer may (or may not) have a theoretical benefit to hypofractionation, but due to the lack of reported data, we can’t confirm or refute this hypothesis.
It seems to me that patients are interested in a treatment approach that employs fewer sessions, but in my opinion that rationale alone shouldn’t be enough for patients to select a less than fully explored treatment regimen for prostate cancer when there are already very successful treatments available, i.e. standard fractionated intensity modulated radiotherapy, brachytherapy, or surgery.
Thanks for the additional insights Dr. Sandler. We appreciate your input.
This is another prime example of financial return driving treatment technology, like proton therapy. Current standard prostate cancer therapy with surgery, IMRT radiation +/- radioactive seed implantation, and radioactive seeds implantation alone are safe and have excellent outcome. While hypofraction may have a biological benefit in treating prostate cancer, the risk of bladder and rectal injury with hypofraction also increases significantly. The current grade 4 rectal injury rate is <0.1%. There is really no reason to put any patient at higher risk without significant survival benefit.
“Is CyberKnife as effective and as safe as other forms of therapy for the treatment of localized prostate cancer? Answer: We don’t know.”
While it is true that the CyberKnife has a more limited track record than some of the other radiotherapeutic methods, due to the relative newness of the technology, there are increasing safety and efficacy data with this method, including a new fully peer-reviewed report from the Stanford group (King et al.) that appeared in the International Journal of Radiotherapy Oncology and Physics “Articles in Press” section. This is the main radiation oncology journal.
In that report of favorable and early intermediate prognosis patients the three-year PSA disease-free survival rate is 100% — obviously not worse compared with other treatment methods. Their reported incidence of grade III toxicity is 5% for urinary complications and 0% for rectal complications — a result that is comparable with other contemporary radiotherapeutic results. The authors have since modified the urethral radiation dose design method to further reduce the incidence of urinary morbidity.
As their median follow-up is 33 months, this result does indeed suggest reasonable safety and efficacy, with the caveat that of course we would like to see a larger number of patients followed for a longer period of time to confirm the findings. The majority of delayed radiation complications manifest by two years post-treatment — particularly rectal complications.
In our own center (CyberKnife Centers of San Diego) we have treated nearly 100 prostate cancer patients with the CyberKnife and although our observations remain preliminary, due to the fact that our center only opened two years ago, there are already two obvious trends in our own patients:
1. PSA response — Our median 18-month PSA level in prostate CyberKnife cases is 0.45 ng/ml and over 90% of the patients have an 18-month PSA level lower than 1.0 ng/ml. This 18-month PSA result is easily competitive with our extensive universe of IMRT and brachytherapy results, and we are particularly encouraged by a very large post-CyberKnife PSA drop-off between the 12-month and the 18-month follow-up interval. In other words, the PSA levels are still dropping impressively at 18 months post-treatment.
2. Toxicity — Thus far our grade III toxicity rate is 1% and the only such case occurred in a high-risk patient that received both CyberKnife and external beam pelvic radiotherapy. Our incidence of grade III complications in CyberKnife monotherapy cases is zero, though again, longer follow-up with a larger number of patients will be required for confirmation.
Finally, to formalize both the efficacy and toxicity observations more definitively, our center is the lead investigator for a multi-institutional CyberKnife prostate monotherapy study with an enrollment target of 253 patients — a study which is accruing well to date.
Our treatment method, incidentally, uses the CyberKnife to noninvasively deliver a radiation dose schedule and dose pattern comparable to that delivered by high dose rate (HDR) brachytherapy — a validated safe and effective prostate cancer approach.
Our “virtual HDR” CyberKnife method in fact has also been peer-reviewed and published in the Red Journal.
Thus far our, pending longer-term confirmation, our safety and efficacy results do indeed resemble HDR brachytherapy very closely ,and yet the patients did not require an invasive hospital-based method to receive it.
Yes, longer-term confirmation of the encouraging preliminary robotic radiosurgery result is necessary before this becomes a “standard” treatment method, but meanwhile, patients who understand the relevent issues are definitely within their rights to consider this treatment method, ideally under the auspices of a clinical trial so that we may formalize the answers as soon as possible.
Thank you for your comments Dr. Fuller. Are you able to provide answers for the second and third questions we originally posed too?
“What is the cost of CyberKnife treatment for localized prostate cancer? Answer: We don’t know, but the equipment alone costs around $4 million.”
There seems to be much confusion about this point and perhaps a misperception that CyberKnife treatment is more expensive. While it is true that the per treament cost of CyberKnife is substantially higher than conventionally fractionated radiation treatment such as IMRT, this difference is offset by the fact that there are far fewer total treatments with the CyberKnife (4-5 treatments) compared with IMRT or other forms of “conventional” radiotherapy (typically 38-45 treatments).
Globally, the cost of CyberKnife prostate treatment is comparable with IMRT or less than IMRT, depending upon the site of service and exact number of treatments applied.
Examples:
- 5 fraction hospital-based CyberKnife cost =~ IMRT course
- 4 fraction physician-office-based CyberKnife cost is significantly lower than a course of IMRT
“Is the average health insurance carrier reimbursing for CyberKnife treatment of prostate cancer? And what about Medicare? Answer: We don’t know, but it would surprise us if they are.”
This has definitely been a problem as many of the private insurers have placed CyberKnife in the “experimental treatment” category. When they do this, typically, the service is not covered.
There has been definite positive insurance movement recently though. To my knowledge, Aetna was the first private insurer to to cover this service, and more recently, Blue Shield of California added prostate cancer to the CyberKnife covered services list. Unquestionably, we are seeing fewer CyberKnife prostate insurance denials now than we were a year ago, though coverage remains insurance company-specific.
In cases where the prostate CyberKnife service was not covered, some of our patients have appealed and had the initial denials overturned, either by higher level review within the insurance company itself, or in some cases, by the State of California Department of Managed Care. Although some insurers still seem to have a “default” no coverage policy, in some cases, with additional information or appeals, their initial denials ave been reversed.
Medicare prostate CyberKnife coverage policy varies by region and almost resembles a blue states versus red states pattern on a presidential electoral map. In other words, it is covered in some regions and not covered in other regions, depending primarily upon their specific “Local Coverage Determination” (LCD) document. An individual patient simply needs to check with their local CyberKnife provider to see whether Medicare covers the service in their state.
The FDA “substantial Equivalence 510(k) approval of Cyberknife K052325 on 9/14/2005 may be found here.
http://www.fda.gov/cdrh/pdf5/K052325.pdf
“The CyberKnife System for Stereotactic Radiosurgery/Radiotherapy is intended to
provide treatment planning and image-guided stereotactic radiosurgery and precision
radiotherapy for lesions, tumors and conditions anywhere in the body when radiation
treatment is indicated.”
–Gerald N. Rogan, MD
Dear Drs Fuller and Rogan: Thank you for this additional and helpful information which certainly will enable interested patients in being fully aware of their therapeutic options.
Can Joseph Chui (8/22/08 above) please elaborate on increased rectal injury w/hypofractionated (CyberKnife) radiotherapy? Is this theoretical or real — because others report no injuries? My Dad is in the midst of deciding on Tx for Gleason 7 prostate cancer. Thank you.
Prostate cancer is the number two cancer killer of men. There is no doubt that millions of dollars are at stake.
What is the motive of CyberKnife critics?
Look at the facts. The medical centers that have treated the majority of patients offer both IMRT and CyberKnife.
What financial benefit is gained by the medical center and the doctor?
1. The medical centers receives less revenue for the 4-5 day of CyberKnife treatment.
2. The doctor receives less pay for 4-5 CyberKnife visits vs 40 IMRT visits.
3. Proton Therapy is the most expensive of all treatments.
4. The patient cost of treatment transportation, food and lodging is much less for the CyberKnife than 40-30 trips or eight weeks in a hotel for IMRT or Proton Therapy
5. The insurer cost is no more for CyberKnife and likely less.
The CyberKnife offers lower cost to all parties, lower income to doctors, easier treatment for patients, in the worst case the side effects are equal to or better than IMRT or Proton Therapy, biological cure is equal or better than IMRT of Proton Therapy. Clearly the CyberKnife is a threat to the market served by IMRT and Proton Therapy.
In my opinion ASTRO is biased against the CyberKnife. And many doctors are not aware of their apparent bias and double standard or may share the same motives. From ASTRO’s website:
“To better educate the patients that our members work so hard to cure, ASTRO works closely with the media to promote accurate articles on scientific breakthroughs involving radiation therapies. We also work with patient advocacy organizations to publish educational materials that keep patients and the public informed about radiation therapy as a safe and effective treatment option.”
The do not mention the CyberKnife as a prostate cancer option in their EB literature and in the clinical trial section no mention of the CyberKnife.
The advertised ASTRO external beam radiation therapies (IMRT and Proton) have not demonstrated superiority for cure or reduced side effects when compared to the CyberKnife in treating early stage prostate cancer. In fact both therapies have higher failure rates at 1, 2, 3 and 4 years. All therapies have varying degrees of urinary and rectal issues at 1, 2, 3 and 4 years. Both IMRT and Proton treatments are more disruptive to the patient’s quality of life and require substantial time away from work when compared to the CyberKnife. And both of these treatments will cost CMS hundreds of millions of dollars if SBRT/CyberKnife treatment is allowed to be removed as a treatment option. ASTRO prostate cancer brochure link follows: http://www.rtanswers.org/brochures/documents/astroprostatebrochure2.pdf
I have additional concerns regarding ASTRO recommendations. When a patient is treated by IMRT the treatment center submits a code for payment. Is the dose received by the patient defined? In fact the dose varies from treatment center to treatment center. Based on the success of treating prostate cancer with higher dose per fraction by the CyberKnife and high dose brachytherapy, IMRT centers are increasing their doses delivered. Do they have short, mid or long term data before treating patients? I would expect these higher doses to be considered experiential treatment, without data proving safety verification or cure rate? There is no specific IMRT treatment plan that corresponds to standard treatment dose. There have been no randomized trials to define what dose is the most effective and the long term risk, or side effects.
An ASTRO presentation (2008) confirms the failure of Proton Therapy show a benefit to IMRT.
“Proton radiation has unquestioned value for treatment of certain rare cancers, said Dr. Zietman. However, the technology has yet to demonstrate any advantages over other forms of radiation therapy for common malignancies, such as lung and prostate cancer, where proton radiation centers would recoup the capital investment.
“The problem is that most patients in the United States treated with proton beam are treated for prostate cancer,” he said. “It’s the economic driver of the proton avalanche.” (http://www.medpagetoday.com/MeetingCoverage/ASTRO/11076)
Without any patient benefit from proton therapy, why does ASTRO promote this therapy which is the most expensive of all options?
I find the ASTRO position for treatment by SBRT/CyberKnife unconscionable and without cause!
As a cancer patient I want all treatment options not the just the ones ASTRO advertises. I feel very strongly about a patients right to make an informed choice for their treatment. Every treatment has risk and from my research every other option has higher risk of death, infection or biological failure. It is the cancer patient’s quality of life that is at risk. It must be our choice in consultation with our doctors to select the treatment that best meets our specific limitations or medical needs.
Do doctors still take and follow the Hippocratic Oath? Do the CyberKnife critics care about their patients’ quality of life? It would seem they are more concerned with the money deposited to their pockets than a man’s urinary function, ED function, cure potential, and/or ease of treatment?
Editorial comment: Fred Kinder (like others) clearly has strong opinions on this subject. On some of these issues we would back him 100 percent. On others, we think he needs to do a little more research. However, we respect his right to express his opinions.
Thank you for all the information provided. My husband just completed three CyberKnife treatments for advanced prostate cancer that had spread to his spine and we are currently in a “wait and see” mode. Your insight is very encouraging.