Proton, HDR Brachy or SBRT - which is best for me?

Newly diagnosed with PC and after spending maybe 100 hours researching options I would REALLY like to hear from some of the experts' on their advice (Tall Allen and others) please. After researching I am considering proton therapy (20 hypofractions at higher dosimetry), HDR brachytherapy or Cyberknife. Not interested in surgery for SE, although I've consulted with some of the top surgeons (Dr. Catalona for RP and Dr. Andrioli LRP). My insurance doesn't cover proton therapy, but it's employer funded so there is a possibility I could get the company to do an override letter (I've been with them 32 years). I want the trifecta plus low rate of recurrence, and feel it's probably a good idea to treat the margins a bit. Would like to use SpaceOAR to save the rectum if possible even though I'll have to pay for it.

Here are my stats/diagnosis, so please advise:
Age 55 and otherwise good health (got over thyroid cancer last year).
PSA scores:
10/1/2014 was 4.3
5/5/2015 was 3.83
5/17/2016 was 6.03
6/13/2016 was 6.27
8/30/2016 was 4.8

Biopsy on 7/11/16 showed 7/12 positive with 1 sample Gleason 7 (3+4) and 6 Gleason 6 (3+3), perineural invasion in 2 samples:
Left lateral base 3 + 3 for 70% and perineural invasion identified
Left lateral mid 3 + 3 for 5%
Left lateral apex negative
Left base negative
Left mid 3 + 3 for 10%
Left apex 3 + 3 for 30%
Right base negative
Right mid negative
Right apex 3 + 3 for 5%
Right lateral base 3 + 4 for 5% (my only 7) and perineural invasion identified
Right lateral mid 3 + 3 for 5%
Right lateral apex negative

Urologist that did the biopsy indicated it was stage 2 and cT1c and prostate is normal size.
I've had 4 docs do the digital exam and indicate they could not feel any lumps, etc.

Report from 3Tessla 3D MRI with/without contrast this week:
There is a midline prostatic utricle cyst that measures 3.1 x 3.1 cm (not sure if that changes anything).
A 1.0 cm (axial dimension) 0.7cc lesion in left medial peripheral zone adjacent to the prostatic utricle cyst at the mid gland. This lesion is dark on T2WI, scores 4 on DWI, DCE is negative. Overall PI-RADS is 4 (I know it's cancer of course from the biopsy). Additional bandlike and geographical areas are seen on T2WI throughout the peripheral zone are without correlated on DWI and not scored by PI-RADS.

Prostate volume 31.1 cc

Staging information from MRI: There is no gross extraprostatic spread of tumor. No enlarged lymph nodes. Normal bladder, bowel and marrow signal.

Impression from Radiologist: The lesion of greatest concern is in left medial peripheral zone at the mid gland and other areas of abnormal T2 (I presume this is referring to the dark bands). There are differences in the biopsy report and MRI suspicious site, and there is more than 1 site of suspicion on the MRI. This uncertainty suggests focal oblation not ideal.

Thanks so much in advance.

Post Edited (Randy Lee) : 9/16/2016 10:16:24 PM (GMT-6)

Hi Randy Lee-

I think proton therapy is a good therapy, it's just no better than other, less expensive therapies. As you said, different SEs are important to different people, For me, the sexual SEs were of paramount importance, so I would never choose protons. What I wrote about it was:

"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."

Proton therapy at University of Florida Jacksonville – 5-year outcomes

(There's a handy-dandy table comparing it to other monotherapies.)

I also think hypofractionated protons is a good idea, if it lowers the cost:

Proton Hypofractionation



You also wrote, "Would like to use SpaceOAR to save the rectum if possible even though I'll have to pay for it. "
I can't imagine why. It doesn't "save the rectum." SpaceOAR solves a problem that isn't there. They acknowledge that it does nothing to reduce acute rectal SEs, which is really the only time one gets rectal SEs. Late term rectal SEs are rare. You can see it in the "proton" table above -- the incidence of serious (grade 3) rectal SEs was zero for both SBRT and HDR-BT, 0.6% for protons, 0.8% for LDR-BT, and 2% for IMRT.

In fact, in the SpaceOAR validation study, only one man with late term grade 3 toxicity made the finding statistically significant. In the statistics world, we call this a lack of "robustness". Apart from the cost of the gel, there is anesthesia (which carries cost and risk) and a transrectal injection (which carries infection risk). Here's my article about it:

SpaceOAR hydrogel decreases rectal radiation dose, but is it worthwhile?

Also, what is the best machine for SBRT now for the trifecta (Cyberknife, TrueBeam, Novalis Tx)?

Thanks again. So based on that SBRT sounds like a good option. I too am concerned with sexual QoL. So Tall Allen, picking your brain again, do you know where the best place in the Midwest is for SBRT, and which machine is best (Cyberknife, TrueBeam, Novalis Tx)? I'm near St Louis but really don't mind traveling for it.

Thanks Michael. Yes, I had a second opinion on the biopsy at Northwestern in Chicago when I consulted with Dr. Catalona, the urologist that has done the most ORP and invented the PSA score. I've thought about AS but I'm thinking of not waiting too long, although it's already been two months. I just need to find the right SBRT location and doc, and I'm willing to travel for the best.

Randy,
I am interested in your decision process, I am somewhat similar except I have 1 4+3 core, plus a 15 PSA, so am probably farther along than you.
I am leaning toward HDA brachy now. As an engineer, this was my thought process
1)Ruled out surgery: Probablity of 70% that mine has spread outside prostate due to Gleason and PSA. My worst case scenario is to have prostate removed, suffer all side effects, then find out still have cancer and need radiation anyway
2) Looked into Proton and experimental Carbon Ion beam, proton not covered by insurance, expensive ,and not in Michigan. Carbon ion very promising, but need to go to Shanghai to get, and still experimental
3) Compared SBRT, HDR, regular photon, and LDR. Feel that regular photon damages more non-cancer tissue, and that LDR and HDR can pinpoint dosage much better. On the chance my cancer has spread, feel HDR is better than LDR since can dose those areas better.

So, am leaning toward HDR monotherapy, realizing I may need some additional photon if has spread.
Would like to not do androgen blocking

Would consider vaccine studies, but most I have found only take late stage metastastic volunteers

Randy Lee-

I was treated with a Truebeam with RapidArc, but I think there are a lot of machines that can do a great job. I like that my machine was faster than CK (about 10 minutes vs about 45 minutes) but that really isn't very important. The CK takes longer because the robot moves around so much and sites the target frequently (which are good things).

I know there was a HW member who had SBRT at Mercy Hospital in St. Louis. He said they also offered HDR-BT at Barnes Jewish. The best HDR-BT guy is in Detroit, Alvaro Martinez. I think he does it in a single visit.

GDS-

you wrote "Feel that regular photon damages more non-cancer tissue, and that LDR and HDR can pinpoint dosage much better." Since you are an engineer, I hope you won't mind me saying that your "feeling" is contrary to facts. I suspect you are misled by not having yet learned what modern IGRT can do. SBRT is accurate to within less than a mm (as is HDR brachy). The dose to healthy tissue outside the prostate is given by the dose/volume histogram, and they are extremely close for both. The urethra gets higher point doses with HDR-BT because the catheters are so hot, and that explains the difference in acute urinary symptoms. But those reactions are transient.

Randy Lee - I did some research into the experience levels of the RO's I saw. One has been doing PCa with CK since 2008, the other since 2011. Both have high success rates along with high patient ratings. Both either are or have been participating in some of the CK PCa research studies, too. The one I chose also has the benefit of having taught radiation oncology at MSKCC for about 5 years, and did residency in RO at MSKCC. I know I won't find 10 years' experience on PCa with CK outside of the pioneers, but I'm satisfied with what I've found.

Tall Allen, also thanks for the tip on HDR-BT at Barnes Jewish. It is actually the Siteman cancer center located on the Barnes Jewish campus, and that is where I had my MRI and last year had thyroid cancer surgery. It would certainly be convenient, and they list themselves as a national leader in HDR-BT. I will need to find out who is the expert there if I go with HDR-BT. Tough decision, but still leaning toward CK at this point. Here is the link to Siteman:
https://siteman.wustl.edu/treatment/siteman-approach/radiation/brachytherapy/

Dr. Kelley Simpson is a RO in Denver if you would like some nice mountain scenery while doing the Cyberknife. Excellent caring staff as well. Dr. Simpson has done a lot of prostates, including mine.

Yes, you are missing how they actually work.

Intensity does vary with distance, of course. That is calculated into the planning whether it is brachytherapy or external beam.

The way external beam (including IMRT, SBRT or protons) gets a higher dose in the prostate and a lower dose outside of the prostate is by separating the source of the beams from many different places. It is only in the places where multiple beams hit the same place (inside the prostate) that the photon or proton dose is high enough to kill cancer cells.

What I tell patients who don't understand the concept is to draw two asterisks ** In the first asterisk, start in the middle and draw 6 lines going outward. In the second asterisk, start on the outside and draw 6 lines that meet at the center. The first asterisk is how brachytherapy works; the second asterisk is how external beam works. You'll notice that both asterisks are identical. The lines are more spread out the farther away from the center you go - that's the dose to organs at risk. The lines are densest at the center - that's the dose to the prostate.

It's kind of like in Ghostbusters where they warn against crossing the streams, except (as they learn) that's exactly what you want with external beams.

/youtu.be/jyaLZHiJJnE

It is actually tremendously more complex than this simple model because the beams are actually shaped and varied in intensity to conform to the shape and depth of the prostate.

The Bragg peak is a theoretical framework. As you know, it means that protons will deposit almost all of their energy where they stop. In actual fact, protons are readily diffracted from the nozzle and spread out from their linear path because the charged particles repel one another. They also generate secondary particles (protons and neutrons) when they interact with matter, and the angular dispersion of secondary particles, and their damage to healthy cells, is unpredictable. In traditional proton centers (like Loma Linda), it gets more complicated, because they intentionally mess it up (spread out Bragg peak) in order to cover more ground in a reasonable time. The newer pencil-beam scanning machines get around that flaw. What we have to look at instead of just theory, is how it performs in real life. As you see, its toxicity is really no better and no worse than other, less expensive and less tedious therapies.

Tall Allen, I found at the top of the link for dcd55 that he used St Louis Cyberknife with Dr. David Morris, so I will follow up with him this week. It would be nice to get this done locally for sure.