Someone in my support group asked about
IMRT plans - either as primary therapy, with a brachy boost, or as salvage. Would they benefit from tracking intrafractional motion too? I think the benefit would be much smaller and there is a lot less risk to not having it. At only 1.8-2.0 Gy per treatment, a lot less damage is done by a single "miss." Tracking once at the start is probably adequate.
There are a couple of treatments - Tomotherapy and ViewRay - that track continuously, but it is questionable whether the CT in Tomotherapy, or the low power MRI in ViewRay have enough precision to keep the toxicity low enough for SBRT.
Allen - not an MD
•PSA=7.3, prostate volume=55cc, 8/17 cores G6 5-35% involvement
•SBRT 7 year results
treated 10/2010 at age 57 at UCLA
•PSA since treatment:
1/11:3.9 5/11:3.0 8/11:3.7 5/12:1.2 9/12:1.3 5/13:0.4 6/14:0.5
• SEs of treatment:
after 2 wks: mild urinary & rectal - last 1 wk
1 yr after: mild urinary