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Posted 6/8/2018 2:43 PM (GMT 0)
Hi Everyone,
I am low grade but at a point where I have to take action soon. I apologize if this has been covered somewhere else on the forum and I am just not finding it, but is there any research supporting IMRT being better than Proton or vice versa? I see a lot of conflicting information online (and some seems self-serving – for example, the Proton center advocating for their method and vice versa).

I had a frustrating meeting at MGH in Boston, where the doctors effectively will not make a recommendation. They said IMRT and Proton would both “work well” – seems like a pretty big decision to flip a coin and pick a treatment, but that’s effectively where things stand. Reputable doctors at a great hospital, but very little in terms of clarity on a decision. Very frustrating to a certain extent, because if it were them, I'm sure they'd pick one vs. the other, and I'd like to know why, as I'm sure it would not come down to a coin toss (obviously being a little facetious here).

In terms of number of treatments, etc. – I am really just looking for information on the success of the treatment and minimizing side effects (combination of the two). If anyone has any insight or has come across independent research I might be missing, I’d really appreciate your help. I really just don’t know how to pick one treatment vs. the other one, when the doctors won’t make a recommendation and there’s so much conflicting data – hoping for some help.

Thank you very much in advance.
Posted 6/8/2018 2:53 PM (GMT 0)
Proton is very expensive and there is little or no evidence that it works better than IMRT. Some insurance plans do not cover proton therapy. Do you know if yours does? If it doesn't, that might make the decision much easier. You might also want to consider SBRT, a newer therapy that can be completed much more quickly.
Posted 6/8/2018 3:17 PM (GMT 0)
I'm looking into coverage soon, but realistically, if there were less risk of side effects, I'd be fine paying out of pocket. Same with number of treatments -- all things being equal, that would become a factor, and yes, less treatments would be better, but effectiveness and side effects are the two factors I really care the most about, and I just struggle with the idea that the two treatment options are in fact equal in those two categories (effectiveness/side effects).

I'll look into SBRT, but not sure that's an option at MGH (which would be surprising, or perhaps more surprisingly, if they do, why it wasn't offered as a potential option). I have also been to Brigham Women's (also in Boston) and SBRT wasn't mentioned there either. Very confusing stuff.

Thank you for your response.
Posted 6/8/2018 3:25 PM (GMT 0)
Nobody knows until we have the result from an RCT comparing proton-beam therapy with traditional radiation. Meanwhile proton therapy must be regarded as a promising, but experimental, expensive alternative. Are you the type of person who often tries new things before others and like experiments?
Posted 6/8/2018 3:28 PM (GMT 0)
Welcome to HW.

Of all the external beam RTs, SBRT is showing that it has few SEs than the others.

Like Fiddle said, the proof is thin that proton is better. However, we do have a number of guys who've gone down that path and were happy with the result.

Still, I recommend at least looking into SBRT, before making a finial decision.
Andrew
Posted 6/8/2018 3:48 PM (GMT 0)
I was in a similar situation a few years ago that you're in now. SBRT was relatively new then and not as many success stories as now so I really didnt consider it then although I certainly would now. In fact today I'd have to be convinced not to choose it.

As you can see from my signature I chose Proton at UFPTI for a number of reasons. I looked into IMRT locally and found a number of excellent large teaching hospitals with excellent IMRT doctors and talked with doctors at Wake Forest Medical Center and Duke cancer center. I then requested a package from UFPTI which came Fedex the next day. It contained 2 books and lots of papers on Proton (promotion material mostly) along with several comparison studies. The most important information it contained was a contact list of several hundred men who had been treated with Proton for prostate cancer. It listed their age, date of treatment, city, email, and phone numbers. I picked about 30 from the list choosing them based on several criteria and called each one. They were all happy to share with me what led them to chose proton over other treatments. My contacts were men from all walks but a lot of engineers, executives, a couple of doctors, one dentist, and a lawyer. They all impressed me as men who did not rely solely on their urologists to have surgery. They wanted to educate themselves on alternative treatments to surgery with equal cure rates but lowest possible side effects. They were all extremely happy with their decision. None had any side effects to speak of even after several years post treatment.

My treatment was paid for entirely by Medicare and Blue Cross supplement. We did decide to stay on Amelia Island during my 8 weeks of treatment and that was my out of pocket. My treatment was a breeze, never tired or any side effects except burning during urination while in treatment. Aleve did not help much but diclofenac did. After treatment I havent had any notable side effects.
Posted 6/8/2018 3:49 PM (GMT 0)
Mike there are a few comparison studies and some NIH research papers on Proton and Photon therapy for prostate cancer treatment. No clinical trials have been completed but they have started these in a number of locations throughout the country. One thing to look at is the QOL outcomes for each treatment and enhancements to treatment that have shown good results. Since you are low grade I would suggest you continue your research especially reading the peer reviewed papers with QOL outcomes. Generally they are very similar, but there are some differences in external and seed implanted radiation QOL results which seem to be effected by the length of treatment and the dose. Also the individual patient's age and prior health issues. I need a treatment that does the least damage to my bladder neck due to scarring. Since I had a TURP in 2003. I also like the results from SpaceOar protecting the rectum and reducing ED. The radiation movement has been to increase dose and reduce treatment time. This is appealing to insurance companies and patients. However, it does have some increased risk to GU. My emphasis besides getting the cancer is to not end up incontinent. When someone tells you there is a slight increase in GI or GU outcomes ask what exactly those are and what was the percentage difference. Studies like this one have been my focus: Urethral Strictures and Stenoses Caused by Prostate Therapy https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5010629/ . I would consider what is important to you in priority order. We know that oncologist and surgeons list is first dealing with the cancer QOL outcomes are secondary. Researchers have found that the better the cancer treating facility the better the outcome. This appears to more important than the treating radiation oncologist. The better facilities are usually university based. I am going with MD Anderson for Proton pencil beam unless I change my mind. I also have started hormones to increase the success of the treatment, as was recommended for me by more than one oncologist. Below is an example of the QOL comparisons in a five year study. Good Luck!

Comparison to other radiation therapies. Someone said that radiation is radiation which is true. However how the radiation is dosed and the length of treatment are important too. I have been recommended for 48 Proton treatments. I would rather have 15. Ha

The following table shows some oncological and toxicity outcomes at 5 years for various radiation therapies as practiced at single institutions in the last several years. While differences in patient selection confound our ability to rigorously compare the therapies, they do show a general range of best-expected outcomes. Until we see the results of large-scale prospective randomized comparative trials, this is about as good as we can do in comparing them.

Proton IMRT SBRT LDR-BT HDR-BT
5-yr bRFS
Low risk 99% 97% 97% 95% 99%
Intermediate risk 94% 94% 91% 89% 95%
High Risk 74% 87% 74% 68% 77-93%*
Late toxicity
GI grade≥3 0.6% 2% 0% 0.8% 0%
GU grade≥3 2.9% 2% 1.6% 7.6% 4.9%
bRFS= biochemical recurrence-free survival

References:
Proton: Bryant et al. http://www.redjournal.org/article/S0360-3016(16)00158-9/pdf: 78 GyE median dose, 15% received ADT
IMRT: Liauw et al. http://tct.sagepub.com/content/8/3/201 :76 Gy median dose, 50% received ADT, 4-year data
SBRT: Katz et al. http://ro-journal.biomedcentral.com/articles/10.1186/1748-717X-8-118: 35 Gy/5fx, 18% received ADT
LDR-BT (low dose rate brachytherapy – monotherapy): Kittel et al. http://www.redjournal.org/article/S0360-3016%2815%2900253-9/abstract: 18% received ADT
HDR-BT (high dose rate brachytherapy – monotherapy): Hauswald et al. http://www.redjournal.org/article/S0360-3016(15)03101-6/abstract: 43.5 Gy /6fx, 9% received ADT, 10-year data.
*For high-risk HDR-BT patients, see: HDR Brachy Boost and Monotherapy for High-Risk Prostate Cancer

Proton therapy afforded rates of cancer control comparable to the other monotherapies. Urinary and rectal toxicity were similar as well. Sexual quality of life deterioration was also similar to what we have seen for IMRT and LDR-BT (see this link). HDR-BT and SBRT seem to be superior in preserving erectile function.

If they can bring down the cost of proton therapy, it can be competitive with IMRT. As with IMRT, hypofractionation (fewer treatments) of proton therapy may deliver equivalent results at lower cost. Pencil-beam proton therapy may be able to improve toxicity still further.

68, PSA 5-18: 12.7, 4-30-18: 13.9, 1-30-18: 13.2, 1-13-18: 13.7, 5:04-12: 2.1
3-month injection of Lupron 5/21/18 Bicalutamide 50 mg 30-day supply
3+4=7 in two cores 2/13/18 or 4+3=7 MD Anderson review of images 5/21/18
1.8 lesion MRI T3 3/27/18 Bone scan clean

Post Edited (SantaZia) : 6/8/2018 10:39:54 AM (GMT-6)

Posted 6/8/2018 3:52 PM (GMT 0)

Gemlin said...
Nobody knows until we have the result from an RCT comparing proton-beam therapy with traditional radiation. Meanwhile proton therapy must be regarded as a promising, but experimental, expensive alternative. Are you the type of person who often tries new things before others and like experiments?

If Proton is to be considered "experimental" than SBRT must also be in that category.
Posted 6/8/2018 5:30 PM (GMT 0)
Neither Proton nor SBRT are considered to be experimental for PCa. Both have been approved for use and reimbursement by Medicare. ASTRO published last year that Proton should only be used in a clinical trial until it was proven to be better than IMRT/IGRT.

Many years ago before IMRT/IGRT it is clear that Proton was superior at providing less toxicity. Since IMRT/IGRT have the ability to more tightly focus the beam similar to Proton, the Proton advantage simply isn’t there. But it generally costs three times as much and Medicare and most insurance will no longer cover the additional cost when there is no proven advantage.

I have also read reports that indicate there is significantly more radiation scatter when the beam enters the body before reaching the Bragg Peak. This scatter means potentially more radiation where you don’t want it and more toxicity than IMRT/IGRT.
Posted 6/8/2018 5:40 PM (GMT 0)
There has never been a randomized comparison of proton and IMRT, but the most recent single-institution studies using the best new machines show there is no difference in outcomes or in side effects between them. Here's some data:

/pcnrv.blogspot.com/2016/08/proton-therapy-at-university-of-florida.html

A lot of patients are deceived by the hype about Bragg peaks. That is only a theoretical framework. In the real world, protons are diffracted from the nozzles, spread out due to charge repulsion and generate secondary particles in random directions.

Many insurance companies will not cover it because it there is no benefit for the increased cost.

Have you looked into SBRT. Irving Kaplan at Beth Israel can do it for you in just 5 treatments. There are also both kinds of brachytherapy that are worth seeking out experts to talk to.
Posted 6/8/2018 6:04 PM (GMT 0)
Thanks everyone for sharing, I really appreciate it. I am in really great health right now (other than this), so yes, quality of life/side effects is what scares me the most.

People seem upbeat about SBRT, so I'll certainly check that out. I find it crazy that I'm first hearing about the option here, having seen so many doctors, and living in Boston (which is reputable in terms of medical), but thankfully, have not committed to a treatment option just yet. Anyone in the New England area that's had this done (SBRT) that would recommend their surgeon/Dr.?

Thanks again everyone -- very appreciative of the messages back.
Posted 6/8/2018 6:06 PM (GMT 0)
Thanks Tall Allen, will check Irving Kaplan/Beth Israel out (sorry, saw your reply after my last post).
Posted 6/8/2018 7:26 PM (GMT 0)
A few people here have mentioned SBRT -- what exactly is attractive about it? That there are less treatments (which for my own personal situation, is irrelevant)? InTheShop, what data are you referencing? The first thing I came across online (American Cancer Society's website) is saying that SBRT's side effects could be worse than IMRT...

https://www.cancer.org/cancer/prostate-cancer/treating/radiation-therapy.html
The main advantage of SBRT over IMRT is that the treatment takes less time (days instead of weeks). The side effects, though, are not better. In fact, some research has shown that some side effects might actually be worse with SBRT than with IMRT.

So much conflicting data, very frustrating. Thanks again everyone.
Posted 6/8/2018 8:11 PM (GMT 0)
Hello Mike and welcome. One of the largest respositories of easy-to-read data is in the blogspots done by member Tall Allen. Follow the link in his earlier post and then looks to the right of the page for the archives. There you will find tons of meaningful and understandable data that may help with your decision. If lack of side effects is important to you, then SBRT is a great alternative to consider. You should also look at HDR Brachy and LDR Brachy. All three of those treatment options generally provide excellent curative potential that certainly rivals surgery, IMRT and PBT. They are all less invasive and "easier" to experience if that is important.

Keep looking at your options. The mist will clear, I promise.

Best of luck,

Jim
Posted 6/8/2018 8:50 PM (GMT 0)

JNF said...
Neither Proton nor SBRT are considered to be experimental for PCa.


Makes me wonder if a treatment can be experimental in Europe and at the same time non-experimental in US?
Two quotes below from the European Association of Urology guidelines makes me believe that on this side of the Atlantic we are somewhat less enthusiastic. Allen, you if any, probably understand this disparity?

EAU Oncology Guidelines Prostate Cancer said...
A RCT comparing equivalent doses of proton-beam therapy with IMRT is underway. Meanwhile, proton therapy must be regarded as a promising, but experimental, alternative to photon-beam therapy.

EAU Oncology Guidelines Prostate Cancer said...
Extreme HFX [Hypofractionation] has been defined as radiotherapy with > 3.4 Gy per fraction. It requires IGRT and stereotactic body radiotherapy (SBRT). Short-term biochemical control is comparable to conventional fractionation. However, there are concerns about high-grade GU and rectal toxicity, and long-term side-effects may not all be known yet. Therefore it seems prudent to restrict extreme HFX to prospective clinical trials and to inform patients on the uncertainties of the long-term outcome.

Post Edited (Gemlin) : 6/8/2018 2:53:56 PM (GMT-6)

Posted 6/8/2018 9:58 PM (GMT 0)
Both Proton Hypofractionation and Photon Hypofractionation (SBRT) can be experimental especially as they increase the dose and reduce the treatment days. The trend is to get the job done quicker with high doses and shorter treatment days. This is attractive to insurance companies and patients. However the longer treatment and lower doses might be better for some patients depending on the individual situation and expected outcomes. What makes this interesting is that it is much more expensive to do the low dose and longer treatment. Here is a recent clinical study. https://www.advancesradonc.org/article/S2452-1094(18)30029-0/fulltext "Dose fractionation for the treatment of prostate cancer has been an important topic of clinical debate. When standard fractionation is used, improved results have been seen with dose escalation.However, treatment duration with some regimens approaches 9 weeks, and concerns about resource utilization and access to care have been raised. Furthermore, dose response curves define the ideal EQD2Gy for prostate cancer as >90 Gy, a dose never reached before, even in the most aggressive dose escalation trials.5 Because the α/β for prostate cancer has been defined as approximately 1.5, hypofractionated regimens can deliver relatively high biologic doses to the prostate for tumor control while maintaining adequately low biologic doses to normal tissue." The devil is in the details!
Posted 6/9/2018 1:08 AM (GMT 0)
Here's the randomized clinical trial proving that SBRT and IMRT were equivalent in toxicity and cancer control. (And this was done with a very lame technique)

/pcnrv.blogspot.com/2018/04/first-randomized-clinical-trial-of-sbrt.html

Gemlin - For prostate cancer, they have been doing protons in the US since 1990, and SBRT since 2003. Both SBRT and IMRT have published 10-year outcomes.
Posted 6/9/2018 1:31 AM (GMT 0)
When I was diagnosed with Gleason 3 + 3 prostate cancer in 2011, some members of the support group I went to tried to convince me that proton therapy is better than other forms of radiation treatment. One of them gave me a book written by someone who underwent proton therapy treatment. That book appeared to me to be a blatant advertisement for proton therapy.

I opted for seed implant. I practically had no side effect. But, unfortunately, I had recurrence in 2016 in a mass outside the prostate and attached to the prostate. The inside of the prostate was found to be cancer free.

If I went for proton therapy, the outcome might have been the same. I really don't regret my treatment choice.

The impression I get is that proton therapy and other forms of radiation treatment have more or less the same outcome. Everybody has to make his personal choice.Cancer is a strange beast. A cancer cell not killed by treatment can multiply and come back to haunt you many years after the initial treatment.

I had cyberknife and ADT for my recurrence. I hope it would buy me enough time to die of something else.
Posted 6/9/2018 1:56 AM (GMT 0)
Hi Mike,

You asked what is so attractive about SBRT -- if it was just the smaller number of treatments. I think that may be the entirety of the advantage. As many people have observed here, IMRT is an endurance test. Five instead of 35 or 40 treatments can be appealing. I've done IMRT and it was no big deal. In my case the radiation center was literally on the way to work, so it was extremely convenient.
Posted 6/9/2018 12:22 PM (GMT 0)
I asked my MD Anderson urologist if proton or photon radiation was more effective, i.e., a better radiation choice. "Radiation is radiation" was his answer.
Posted 6/9/2018 1:39 PM (GMT 0)
when I ask my RO about IMRT vs Proton he said, "Neither is going to give you x-ray vision or cause you to glow in the dark."
Posted 6/9/2018 7:23 PM (GMT 0)
TA - Can you help us with the reference to the study (or studies) that showed that fewer fractions at higher dose per fraction actually could have superior disease control for PCa? I remember reading the articles, but don't have the link.

So, fiddlecanoe, there may be more to the IMRT vs. SBRT comparison than number of treatments. SBRT is felt to have greater efficacy (better disease control) and potentially fewer side effects due to tighter beam focus than traditional IMRT. The typical SBRT dose pattern is very similar to that of HDRBT, which has been shown to have about the best disease control stats of any of the radiation monotherapies.
Posted 6/9/2018 9:36 PM (GMT 0)
Mike you started a great conversation. There isn't one PC treatment modality that fits everyone. This is from a recent paper of the QOL outcomes and the costs. Use, complications, and costs of stereotactic body radiotherapy for localized prostate cancer Joshua A. Halpern MD Art Sedrakyan MD, PhD Wei‐Chun Hsu MS Jialin Mao MD, MS Timothy J. Daskivich MD, MPH Paul L. Nguyen MD Encouse B. Golden MD, PhD First published: 25 May 2016 https://doi.org/10.1002/cncr.30101 Full Text available Wiley Online Library. "A total of 542 men received SBRT, 9647 received brachytherapy, 23,408 received IMRT, and 800 men were treated with proton beam therapy. There was a significant increase in the use of SBRT and proton beam therapy (P<.001), whereas brachytherapy use decreased (P<.001). A higher percentage of patients treated with SBRT and brachytherapy had low‐grade cancer (Gleason score ≤ 6 vs ≥ 7) compared with individuals treated with IMRT and proton beam therapy (54.0% and 64.2% vs 35.2% and 49.6%, respectively; P<.001). SBRT compared with brachytherapy and IMRT was associated with equivalent gastrointestinal toxicity but more erectile dysfunction at 2‐year follow‐up (P<.001). SBRT was associated with more urinary incontinence compared with IMRT and proton beam therapy but less compared with brachytherapy (P<.001, respectively). The median cost of SBRT was $27,145 compared with $17,183 for brachytherapy, $37,090 for IMRT, and $54,706 for proton beam therapy (P<.001).

CONCLUSIONS
The use of SBRT and proton beam therapy for localized prostate cancer has increased over time. Despite men of lower disease stage undergoing SBRT, SBRT was found to be associated with greater toxicity but lower health care costs compared with IMRT and proton beam therapy. Cancer 2016;122:2496–504. © 2016 American Cancer Society.

Since I am 68 and have Medicare and a supplemental policy I think Proton Pencil Beam might be the best for me with my prior TURP and scaring. I wouldn't necessary have needed to add hormone treatment but the research indicated it would improve the outcome. Also adding SpaceOar too to reduce side effects. A really good PC surgeon told me he would not recommend surgery me as there was too much risk of side effects. That was good enough for me. My GP told me if I could afford the best treatment and I could handle being away from home go with MD Anderson as they were customizing the treatment to my needs. My two other consults with radiation oncologists were just giving me the standard treatment they do for everyone. Vist with doctors at as many top notch facilities in the Boston Area that you can. Good Luck!

68, PSA 5-18: 12.7, 4-30-18: 13.9, 1-30-18: 13.2, 1-13-18: 13.7, 5:04-12: 2.1
3-month injection of Lupron 5/21/18 Bicalutamide 50 mg 30-day supply
3+4=7 in two cores 2/13/18 or 4+3=7 MD Anderson review of images 5/21/18
1.8 lesion MRI T3 3/27/18 Bone scan clean
Posted 6/9/2018 10:20 PM (GMT 0)
I'll have some more longterm data shortly.

One has to be careful about using retrospective database data on toxicity like the one SantaZia quoted. It is all but useless. There was an attempt to use patient reported outcomes, which is MUCH better:

/pcnrv.blogspot.com/2016/08/ldrbt-imrt-and-sbrt-quality-of-life.html

A similar methodology was used in a study comparing SBRT to moderately hypofractionated IMRT. This article explains why results were as good or better with SBRT:

/pcnrv.blogspot.com/2016/12/sbrt-vs-moderate-hypofractionation-same.html

However, even that is inferior to a randomized comparison. There was a "treatment regret" study among all patients receiving SBRT, IMRT, and HDR-BT at UCLA, but I think the superior outcome for SBRT had every thing to do with the care Dr King takes in making sure patients know what to expect:

/pcnrv.blogspot.com/2017/01/less-treatment-regret-with-sbrt-and.html

As for oncological outcomes of SBRT, the multi-institutional study (309 patients at 21 institutions) showed that SBRt had a 5-year biochemical recurrence free survival rate of 97% for both intermediate risk and low risk patients, which is as high as anyone will ever get. The toxicity was extremely low:

/pcnrv.blogspot.com/2016/09/5-year-sbrt-trial-high-cancer-control.html

To my mind, the really interesting potential of SBRT is for high risk patients because the biologically effective dose is so high and the toxicity is so low. It will be several years before we have good data on that question.
Posted 6/10/2018 3:38 PM (GMT 0)
Mike this is from Healthunlocked another discussion board. In two weeks, Malecare will be hosting a Live Youtube Show with a prominent radialogist about "Cyberknife." Please email your questions to me and I will make sure they get answered ... email to darryl @ malecare . org Subscribe to the Youtube channel so you don't miss out...go to youtube.com/malecare and click on "subscribe" It's taken us a few weeks longer to get this channel up and running, as we have been struggling to find a quiet space that we could afford. So, please email all of your questions and I will get you the answers.

(I've "obscured" your email a bit with some spaces to prevent the bots from getting it. We have a strong suggestion on the forum that you put email addresses in your profile, and refer readers to that. This makes sure that the reader is at least a member. - 142)

Post Edited By Moderator (142) : 6/16/2018 7:01:25 AM (GMT-6)

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