Meridian Viewray is toast. Can Cyberkife machines use MRI the same way?

[Cancer2x]

Just was unenrolled in a Phase I clinical trial using the Meridian Viewray machine at Dana Farber. Meridian went belly-up in the summer, and the hospital (Brigham and Women’s in Boston) will cease using that machine in October 25th.

Looking for substitutes. Thinking that Cyberknife machines can also deliver IMAGE-guided SBRT, maybe. Can they use MRI, instead of CT, which has a worse record of SE’s, per the MIRAGE trial?

Also - one of my cancerous lymph nodes is REALLY close to my bladder. Has SPACE-OAR Gel ever been used to help separate structures internally other than the rectum?

Questions, questions.

Hoping to find an acceptable radiation treatment and delay ADT as long as possible!

Thanks for any info/ideas!

[dudubaya]

AFAIK only Elektra and Viewray have MRI-LINACs, other vendors like Varian or Cyberknife have on board CT and not MRI, these are not 100% real-time image guidance like MRI-Linacs. The RO will use a fusion of external CT + MRI + PET Scan for the planning part and check the alignment using the onboard CBCT just before delivering the dose. There is no real-time CT imaging and tracking during the dose delivery as per my understanding

[Tall_Allen]

Only Elekta Unity uses MRI. But why are you fixated on MRI rather than CT?

[Cancer2x in reply to Tall_Allen]

This was interesting to me.

Data from the phase 3 MIRAGE trial

(NCT04384770) published in JAMA

Oncology found magnetic resonance imaging (MRI)-guided stereotactic body radiation therapy (SBRT) delivered with MRIdian was superior to computed tomography (CT)-guided SBRT in reducing acute genitourinary (GU) and gastrointestinal (GI) toxicity associated with localized prostate cancer.1,2

"To our knowledge, this trial is the first phase 3 randomized controlled trial comparing MRI guidance to CT guidance

[Tall_Allen in reply to Cancer2x]

Yes, but... You can always reduce radiation toxicity by reducing margins. They compared 4 mm margins to 2 mm margins. (Also, there was no intrafractional tracking on the VMAT linac - which I can't explain). Even so, toxicity was only reduced at 1 month. By 3 months, they were equivalent. In addition to the short-lived toxicity advantage, did patients sacrifice oncological control by reducing margins?

[Cancer2x in reply to Tall_Allen]

Looks like I might be getting SBRT with CT and AI planning using the current ETHOS machine to deliver treatments, 5 sessions, every other day through two weeks. The Varian machine literature, study and outcome reporting from the NIH, and large Australian and Indian outcomes all look like this seems the next best option for me.

I will be discussing my case with the RO for Brighams tomorrow. If I feel good after that meeting, treatment planning will commence on the 18th, treatment starting next day.

Wish me luck. This is terrifying.

[tayninhtom]

Best SBRT I know of is with Paul Okunieff, UF Radiation Oncology Gainesville Fl. I had a para-aotic lymph node 1 mm from the small intestine. Paul said "If you don't move, I'll get it". He did.

[j-o-h-n]

French?

Good Luck, Good Health and Good Humor.

j-o-h-n Wednesday 10/11/2023 5:05 PM DST