Exploring Cyberknife SBRT

Had an encouraging meeting with the radiation oncologist at UCSF today, Dr. Gottschalk, and got a good overview of the Cyberknife treatment. He's done 250 over the last 10 years, mainly in the last 8 years, with results matching or better than other options (only 4 PSA failures, all distal). The treatment seems attractive with only 4 sessions, 9.5 gray each, over 2 weeks, and somewhat less chance of side effects.

I think now I have ruled out LDR Brachytherapy since out daughter-in-law just became pregnant and it would be a worry for her to have to keep physical distance. Plus there's all the other grandkids I couldn't have on my lap. It'd be worth it if there was a significant advantage to Brachy but the doesn't seem to be for me. I also asked about the HDR Brachy he said with G7 they wouldn't do it (usually for higher risk cases I think).

There also doesn't seem big difference between the results from SBRT and standard fractionated IMRT, at least with the indications they have so far over nearly 10 years. That also leans me towards the 4 sessions rather than 44.

So the main choice looks like between Cyberknife vs. RALP and I'll have to mull it over.

In any case it seems there's no big hurry and next spring or even summer would be fine he said. I'm still waiting for the Prolaris score which may or may not be helpful, and will have some imaging (MRI or Ultrasound) after the New Year.

i've read some of the Cyberknife stories here so thanks guys....A couple of things. Somewhere I read a critique that there's "no long term follow up" but Dr. Gottschalk was saying PSA tests every 3-6 months so I'm not sure what that complaint is.

Aside from the relative newness of the treatment and not having the "clarity" of a post-op pathology report (which could also miss things), are there any other main downsides to the Cyberknife approach?

When you said...
i've read some of the Cyberknife stories here so thanks guys....A couple of things. Somewhere I read a critique that there's "no long term follow up" but Dr. Gottschalk was saying PSA tests every 3-6 months so I'm not sure what that complaint is.

I would have thought that they were saying that, since Cyberknife is a relatively new treatment they don't have much data on what sort of problems might occur, say, ten or fifteen years out. Since Cyberknife does a good job of sparing other tissues you would expect that long-term toxicities would be few and minor but there is no way to prove that yet.

I was also a G7 and looked into SBRT earlier this year and seriously considered it. I opted for HDR Brachy, in part, because as a G7 it was going to require petitioning from doctors to try and have my Health Care provider cover me for SBRT - I was warned they would not routinely do so. They might have eventually agreed to do so, but at that point after spending time on my research I was anxious to treat.

If it hasn't already been checked, you might want to confirm that your provider would be willing to cover you for an SBRT.

As PDA said, the term "long term follow up" is research-speak for clinical trials with published long term results, and does not refer to the follow up of individual patients. SBRT has published results with follow up of 7 years (see links in my signature). The longest follow-up for IMRT is 10 years, but that only includes 8 patients! Dr. Katz's numbers - cancer control and toxicity - are very stable. I've seen his 8 year results, and they are nearly identical. I don't expect there will be any surprises.

For all kinds of radiation, we look at "acute toxicity" and "late-term toxicity." Acute refers to those symptoms that appear soon after treatment, usually within the first 3 months. Late-term toxicity refers to symptoms that appear from 6 months onward. With radiation, late-term toxicity - rectal, urinary and sexual - almost always occurs within 2 years of treatment. This contrasts with what many patients are told by poorly-informed urologists or on random places on the internet.

Gottschalk uses a very hefty dose - 40% higher than Katz uses. What is his rationale for that? What kind of toxicity is he seing?

Thanks, Nomar. I didn't succeed

Let me know when. Maybe we can meet for coffee.