Interesting trial: SBRT before prostatectomy

For high risk patients, this looks like an interesting option

https://ascopubs.org/doi/abs/10.1200/jco.2019.37.7_suppl.tps137

JNF said...

This study, in my opinion, seeks to continue to support surgery even though there are equally effective non-surgical treatment methods. It appears to me, the use of pre-surgery radiation is a professional admission that the surgery will fail in treating high risk PCa.

I look at it the other way. The more options available to a patient, the better.

JNF said...
It appears to me, the use of pre-surgery radiation is a professional admission that the surgery will fail in treating high risk PCa.

Uh, that's naïve. It's important that you break your belief that one-size-fits-all in the PC world and that such "blanket" statements fit real life. There is a very wide range of cases diagnosed as "high risk" (about 15% of PC cases) and therapies can be and should be tailored to individual case details.

A case diagnosed with systemic metastasis--which is at one extreme of the high risk range--is a great illustrative example to speak of here...surgery (alone) to remove the prostate is not going to "cure" the patient of the disease, but more cases are local than systemic. Patients with highly aggressive tumors may benefit from combined modality treatment of surgery, radiation, and ADT, similar to that in other disease sites such as rectal or breast cancer [see reference doc in PubMed: "'High-Risk' Prostate Cancer: Classification and Therapy".] The first principle for any therapy plan/any risk-classification is that treatment of the primary tumor is paramount: not only for local control but also to prevent further seeding of distant metastatic sites.

This (OP topic) has the potential to be an excellent new tailored approach for a subset of "high risk" PC cases...another arrow in the quiver.

More broadly though, RP is a second option for patients with high risk PC, as noted in the NCCN, AUA, and European Association of Urology (EAU) guidelines. Studies reported from a number of institutions (see data in the link, above) show 5-year PSA relapse–free survival rates ranging from 55%–71% and 10-year prostate cancer–specific survival rates from 72%–92%. The rates vary as a function of disease extent, but you should check these results against your "blanket" statement above in red.

Lose the "one-size-fits-all" mentality.

Post Edited (Blackjack) : 8/1/2019 11:52:49 AM (GMT-6)

IDK if it's a "superior" opinion...but it's consistent with PC medical professionals, which ignores novice shooting-from-the-hip.

I guess that you didn't notice this is a modified dose escalation study, all below the King/UCLA protocol for primary prostate SBRT treatment. They are aware that the prostate won't quite turn to mush with these low doses, but they want to see how mushy it gets. So your linkage to post-RT salvage RP is moot/not relevant.

BTW, there ARE a few surgeons who will carefully select appropriate patients to do RP by hand after the full-dosage, primary RT treatment (again, not the same concept as the OP's posting). You'll typically only find surgeons willing to do salvage RP post-RT at specialized medial centers. Most surgeons will not attempt it because of the much higher risk of complications and intra-operative injuries, but a few will. After primary radiation, when a surgeon goes in to take the prostate out, he sees a large ball of scar tissue that the bladder, rectum and prostate are in there somewhere but it's hard to distinguish the 3...the tissue planes (separating organs) are obliterated from typical external RT treatments. Too aggressive and you damage bladder and/or rectum; too conservative and you leave behind tissue containing cancer. Complete loss of erectile function and long-term incontinence are commonplace after SRP. Good luck with that!

Bigger picture: Patients who "fail" RT (using Phoenix definition of nadir+2) have only a small chance (according to Eastman, who does SRP) of local-only recurrence which could be "cured" by a local-only surgical procedure.

So, this (in red) is certainly not even close to being correct (or well thought-out):

JNF said...
And now lets discuss the nearly universal statement surgeons say to prospective patients that when surgery fails we can use salvage radiotherapy to try again to cure, but if initial radiation fails you can’t then have surgery. I guess this study sure puts thousands of surgeons at odds with their previous advice.

The nearly universal statement remains substantially intact.




BTW, another set of doctors (Glicksman, et al, including Klotz) tried this more than 15-years ago (2001 to 2004; PreORT study), but they included unfavorable-intermediate risk patients in addition to high risk PC patients...same 25 Gy delivered in 5 consecutive 5 Gy fractions, followed by RP 14 days later.

These doctors just published (May 2019) the long-term toxicity results which reported “unexpected high rates of late GU toxicity,” ie. radiation late-term side effects. They went on to say that “future studies examining the role of RT preradical prostatectomy must cautiously select RT technique and dose schedule [purpose of the current study]. Importantly, long-term follow-up data are essential [to gauge late-term RT effects] to fully determine the therapeutic index of PreORT in the management of localized disease.”

So they concluded too many late-GU toxicity issues...but maybe for the higher-risk patients that's an acceptable trade off. As Fairwind has said, “..You get braver as your options dwindle." It's my hope that with 15 years of additional institutional knowledge, the current results might show improvement.

Post Edited (Blackjack) : 8/1/2019 2:42:50 PM (GMT-6)

Surgery after radiation is very difficult. Margin are unclear, and large areas of scare tissue. My oncology urologist that was trained at MD Anderson that is an extremely skilled surgeon and is one of a few that perform such surgery here in this area. He said patients can expect worse side effects including severe incontinence, and colon damage which sometimes requiring colostomy. I wouldn't even want to go there!

Surgery after regular radiation is very difficult, but this is SBRT, a far morel precise form of radiation. My guess is that it is planned carefully to ensure that it doesn't affect the prostatectomy, while giving the positive effects of adjuvant radiation. Because the prostate is coming out from surgery anyway, they seem to use SBRT to target an area quite close to the prostate where there was EPE (these would be cT3 cases). They mention that they are able to aim carefully because the prostate is still there.

JNF said...
Are we sure you are not him?

Who is this “we” you speak of, Ke-mo sah-bee?