RO wants to do a 2nd sim tomorrow, 1/3 of the way into my treatment

[duckcalldan]

He says that my rectum, for whatever reason, is getting exposed to a bit too much radiation. And that I need to be re-SIMed so that the rays can avoid that area more effectively. Is this a normal thing? On the one hand, I’m thrilled that my RO wants to avoid my rectal side effects. But I would think that the TrueBeam would be able to make on the fly adjustments to do the same thing without a need for a new CT sim.

I’m not questioning his decision; just looking for some info.

[Tall_Allen]

Good RO! There is a new idea called "adaptive planning" that makes changes to the plan as organs shift around and become inflamed. Without adaptive planning, adjustments are made between sessions to irradiate the prostate if it conforms to the shape and size of the plan, but if it changes too much, the planned beams may miss their target. The new MRI linacs make it much easier to do, so I expect we'll see more of this done in the future.

[podsart in reply to Tall_Allen]

If one wanted to check which linac being used conforms to your ref “new MRI linac”, which identifier linac names would confirm it’s the linac you want?

[Tall_Allen in reply to podsart]

Viewray MRIdian and Elekta Unity are the only two I know of. But adaptive planning is rarely done.

[podsart in reply to Tall_Allen]

thanks

[rickyfish56]

I was getting close to the last week of 6 1/2 weeks of IMRT treatments for Bio Chemical reoccurance of my Gleason 9 cancer. My excellent, world class Radiologist at OSHU in Ptld Oregon, after my being sent home a couple of times not treated - because my " Intestines" or othe internal parts would of been in the field of radiation - either because of gas or just a re- shifting around - said " We are going to "re-map" your treatment plan tomorrow.

Of course I freaked out - " isnt this delay going to cause the cancer to grow stronger" , etc, to which he replied " Not an issue - much better for your future health to remap now - versus possible damage later"!

So, no big deal, re- mapped, finished my treatments a few days late -just had 2nd year checkup after radiation - PSA undetectable- No sign of disease at this time. Also no issues with my last 2 treatments after the re-mapping!

Praise the Lord, and Dr. Hung at OSHU!

[maley2711]

At approx the midway poiint of my 28 session RT at Kaiser, my RO did the same, based on his observation that, for whatever reason, my bladder filling was not entirely adequate....and I drank a LOT LOT of water!!!

8 months after RT, so far so good mostly.

I had a new CT for planning, but not a 2nd MRI...so I don't believe what I had would be considered adaptive planning? It was conventional IMRT hypofractionation, with no fiducial markers. The RO used several calcium deposits as fiducials

[tunybgur]

8 months after radiotherapy my bowel and bladder are still quite damaged.

I suffer nocturia, don't remember what a full night's sleep was like, I'm constipated because my natural peristalsis has stopped, and I have to take Laxido to try and get some movement, and there's lots of blood in my stools.

ADT has robbed me of my energy.... I now wonder if the cure is worse than the disease..

Before the RT everything was working fine, am I just unlucky or is this par for the course?

[j-o-h-n]

Geez dan, all the doctor is asking you to do is to duck....to save your ass....

Good Luck, Good Health and Good Humor.

j-o-h-n