First post in Isocentre (need opinions)

Summary:

Node positive prostate cancer

First post in Isocentre (need opinions)

Alfonso Gomez 14 Feb 2011 22:13

65y man.
Gleason 8 (4+4), iPSA 24ng/ml.
Bone scan negative. CT scan: 2 common iliac positive nodes.
KPS: 90%.
For sure ADT, but… what about EBRT?. If yes, which dose to prostate, and nodes?
I was thinking in 46Gy to Whole pelvis, boost to positive nodes to 60Gy, and prostate/seminal vesicles to 74-76. Does it make any sense to escalate doses to prostate?
Another concern, important obstructive symptoms, IPSS:25.

I'd really appreciate comments on this.

Re: First post in Isocentre (need opinions)

Nikhilesh Patil 15 Feb 2011 00:04

Thanks for the post Alfonso,
Here in London,Canada we do:
High risk: 76 Gy to ctv76 (prostate + 1 cm proximal SV), 50.4 Gy to ctv50_4 (pelvic nodes + distal SV) in 35 fractions.
The margins from CTVs to PTVs with daily CBCT imaging guidance are:
ptv76: 1 cm sup, inf, right, left, 0.7 cm ant, post.
ptv50_4: 0.5 cm in all directions.

Nodal volumes contoured as per RTOG consensus guidelines

It will be nice to know if others are doing it differently. Will await response.

Last edited on 15 Feb 2011 00:06 by Nikhilesh Patil Show more

Re: First post in Isocentre (need opinions)

AAM 15 Feb 2011 11:40

boost the common iliac nodes to 76Gy?

Re: First post in Isocentre (need opinions)

Indranil Mallick 15 Feb 2011 17:32

Do the common iliac nodes technically qualify as regional disease? Aren't they outside the pelvis? By AJCC staging common iliac node involvement would be 'non-regional' nodes and be staged as M1a along with paraaortic, inguinal, cervical nodes etc. Is there any evidence for curative intent RT in this situation?

Last edited on 15 Feb 2011 17:40 by Indranil Mallick Show more

Re: First post in Isocentre (need opinions)

Ayan Basu 17 Feb 2011 08:46

Dear Nikhilesh,

If you are doing SIB - 5040 cGy in 35 # seems a bit on the lower side from the BED standpoint for the pelvic nodes and distal SV, specially for the low alfa/beta why do you prefer such a low BED and not go for a phased IGRT with 5040cGy in 25-28# and then boost to the prostate and proximal SV with margins upto 7600cGy @ 2Gy/#is there a specific reason to avoid phased IGRT ?

Last edited on 17 Feb 2011 08:49 by Ayan Basu Show more

Re: First post in Isocentre (need opinions)

Alfonso Gomez 15 Feb 2011 21:16

Hi Indranil,
I was considering this patient a borderline in terms of loco-regional vs spread disease. Anyway he will be staged as stage IV. Not sure if there is a roll for RT, and for this reason one of my concerns is the dose and toxicity!

Re: First post in Isocentre (need opinions)

Nikhilesh Patil 18 Feb 2011 05:09

Hi Ayan, very good point, this is the GU site group approved regimen for our centre, I will ask our GU site group leader if he has any explanation.