65/M
Good GC
Ca rectum post APR in Dec 09
pT3pN0
Completed 4# FOLFOX 4
PET CT s/o perineal recurrence
Surgery not feasible.
Concurrent CTRT advised by suregon
What should be the dose of RT?
Is there any role of brachy?
To fit this patient in some evidence based oncology the only prospective PH III data that i can see fitting in this scenario needs to be deduced from a small subgroup analysis of this trial.
http://jco.ascopubs.org/cgi/content/full/26/22/3687
The easiest thing to comment here would be dose which is 50 Gy, assuming you would ask your surgeon again about resection which means you give Preop CTRT now and then assess response with repeat CT PET 4-6 weeks post CTRT.
You can of course use capecitabine with RT, and dont ask for evidence for this. Damn, Xeloda is just not licensed for this.
Many may simply want to use 5FU with RT which is absolutely fine and evidence based of course.
If surgery is never gonna be a possibility, then perhaps we are talking about Definitive CTRT, in which cases you may have to provisionally think about a Boost to this recurrence. This may be via Brachy or Ext Boost. (10 Gy)
I am not sure any one in this Forum would be able to comment on Primary Radical Brachy without having looked at the PET images.
More so i m not in favour of this as Primary treatment. As boost is OK.
The biggest worry for me is what volumes what you be marking esp CTV if you are doing 3DCRT
or what Borders will you be marking if you doing simple Sim based planning.
Hint:
1. This chap has had APR, many things are out already. Does he have any lymph nodes left. If so, which ones. Are they at risk so as to be included in your CTV. Have we thought about Collateral Lymphatic drainage like we do in testicular cancer. Like for eg the inguinal region would be at some risk. Got no figures for this risk at this time.
2. His disease free interval is less than 6 months.
or should be having Simple straight forward RT … just treat the 3 or 4 cm PET visible disease, forget about the rest.
Toxicity is a new topic by itself, but not relevant here at the current time but could be taken forward.
Unfortunately, i have more questions than answers this time.
Hi Nilesh,
Start off with whole pelvis, conventional #, 5000 cgy chemo RT. Assess response and then decide about boost. Brachy implant after APR sounds challenging. Personally I would go with what Rohit is suggesting, external boost total dose 60-62 Gy.
you don't say why surgery is not feasible and how big the disease recurrence is. Got a picture?
My initial thoughts are:
The choice of dose is controversial. This is one of those circumstances which doesn't occur that often and so the literature isn't that helpful except to say that benefit is possible. We can predict a dose response. The studies are unhelpful because firstly they aren't that common and secondly they usually aren't aggressive.
Does it matter if you give 78Gy and it fails?? Now I AM NOT SUGGESTING THAT YOU GIVE 78GY! Did you get that?
I am suggesting that you put some expectations down on paper, which may be not better than "a feeling in your water". Then look at the three possibilities above - alive, alive with long terrn LENT, dead after substantial LENT - and pick your own poison! Maybe even present the choice to the patient and see what they take.
Anyway that's what I'd do, but I'm not your average RO either (I hope).
Interesting thoughts Andrew.
If you thought of treating the Whole pelvis like Nikhilesh, stick with Ph 1 and Ph 2. 50 Gy + 10 Gy
If you have thoughts like Andrew, i agree sky is the limit, you have ammunition to bombard, but realistically speaking is there any evidence of dose escalation beyond 64-66 Gy in Rectal cancer. As beyond these doses, i m not sure of the enhancement in local control, but i m quite certain of creating a Big hole in the perineum, which this poor chap will have to live with. The probablity of harm far exceeds the probablity of benefit.
Thank God you suggested in Bold of not giving 78 Gy, as that would ensure somethinglike this may happen
http://www.infrastructurist.com/2010/06/01/when-entire-city-blocks-collapse-the-guatemalan-sinkhole/
Bythe way, did any one notice and question why a pT3 No Rectal cancer has recd 4 # FOLFOX chemo ?
Any high risk features Nilesh is hiding ?
not that its gonna change his prognosis and mgt, its just the simple dissection of cases by oncologists.
Andrew do you know any of these guys from Peter Macculam
http://www.redjournal.org/article/S0360-3016(97)00315-5/abstract
Nilesh there are some borders mentioned in this very old paper, let me know if you need full text.
It basically mentions of treating whole pelvis.
Wonder in these modern days of PET scan, would irradiating the pelvis be necessary, just a thought
may be , or may be not ! Just feel like tossing a coin at the end of the day.
Michael J. Guiney & Sam Ngan went off into private and are hypo-publishers now. David Blakey was at PMCI until recently.
The pelvic fields would have been 1.5cm outside pelvic side walls, on L5/S1 and down to anal marker (with bum) or 2 cm below perimeal scar marker. The shielding woul then have taken an approximate 4 x 4 cm triagle off the top R & L corners, and a triangular sliver from central axis mark on the lateral pelvic field down to 4cm in from the lateral lower field corners. This would form an skew-iff octagonal shape. The lateral field had a posterior margin 1.5cm behind the posterior most portion of the sacrum and running through the mid femoral heads. The field was shaped to take out the tissue more than 1.5cm behind the sacrum. The anterior border might be shielded with a triangular area from 4cm in front of sacral promontary along a line down to the top of the symphysis pubis.
I wouldn't automatically conclude that these are the fields I must use. At this time PMCI was using field-based planning for radiotherapy with conventional simulator and possibly event 2D planning (?Theraplan). You are much better able to inform your volumes with CT/MRI and PET.
[I have pulled up the article and copied the text with instructions - looks the same!]
As I said before, pN0 originally, had chemo and still PET-iN0 - I would leave the pelvis alone. Other issue is that the recurrence is very soon after surgery - aggressive or implant/positive margin??
