Post RP, MRI or mpMRI imaging?

RO prescribes ordinary MRI for sRT planning. I have read a number of papers showing preference to mpMRI for its DCE (Dynamic Contrast Enhancement) component, as an aid for resolving false positive ambiguities. Any personal precedents will be much appreciated. TIA.

[Tall_Allen]

Radiation planning is usually done with MRI and CT, both or either. The goal is to contour where the radiation is going, not to find cancer.

[Hidden in reply to Tall_Allen]

Thanks TA but my interest, as noted, is for personal precedents. Theoretical reasoning is nice to know but at the end of the day I will do what makes more sense to me. I am not the type "I have confidence in my drs and do as they say". In fact the one such I knew is now RIP.

[Tall_Allen in reply to Hidden]

What I'm saying is that you are confusing two things:

(1) imaging to find cancer (which is used to guide biopsy)

(2) imaging for radiation planning (which is used for beam contouring)

The purposes are different.

[Hidden in reply to Tall_Allen]

Killing two birds with one stone is not invented yet. Hopefully, my RO sounds better than that Said that if something shows up will get a larger chunk of the radiation dose.

[Tall_Allen in reply to Hidden]

So what you are trying to do is identify cancer in the prostate bed and lymph nodes and give higher doses to those? (This is called "dose painting" or a "simultaneous integrated boost.") It is unknown whether it improves outcomes. Some use PET imaging for this, which has better sensitivity and specificity than mpMRI. However, at low PSA, PET isn't very sensitive. For the prostate bed, the best way to detect areas to obtain a boost dose is at the site of the positive margins, if there were any. For pelvic LNs, a Combidex MRI, available only at Radboud University, exceeds the sensitivity of PET scans,

[Hidden in reply to Tall_Allen]

Wholeheartly agreed. The economics of it:

a) MRI is free

b) mpMRI upgrade add 200 Euros

c) PSMA PET/CT = 1800 Euros

d) Ferrotran MRI = 4000 Euros + travel expenses

All counted in in an accending manner.

The most expensive and difficult to find part is a RO that can read all these having also access to the latest breed of lineac with enough precision for realization. Otherwise it is money thrown out of the window.

But we have diverted from my original call for personal presedents. Let's go back there.

[Hidden in reply to Hidden]

An update for anyone interested.

I opted for an mpMRI instead of an MRI that the RO prescribed. Yes, I am my own advocate and follow my own judgement. Had to pay 150 Euros out of pocket for the upgrade. The finding is a "very suspicious ~6mm mitotic focus" at the anatomical level of the base of the (preexisting) prostate on the left side. Interestingly enough and under my very limited anatomical knowledge, this is adjacent to my left seminal vesicle which had been found invaded during RP. My current PSA is only 0.05. I asked for the MRI when I saw it rising steadily from 0.02 . I am forwarding the mpMRI images to get a second opinion, as false positives have their chances.

Take home message: Blanket statements of the sort: "MRI shows nothing at low PSA levels" have limited application. Better stay vigilant for an early warning!

[Hidden in reply to Hidden]

Update on (blinded) second opinion.

"Status post prostatectomy. No suspecious residual tissue seen in the surgical bed"

Go figure...