Greetings to All!
This particular topic of treatment coordination (or scheduling) of radiation events continues to trouble me somewhat. As many of you already know, my RO has proposed a three-pronged (so-called 'triple-play'), approach to my treatment, involving ADT+LDR-BT+IMRT, and he has proposed that they be performed in that specific order (i.e., LDR-brachytherapy 'before' IMRT, not after). And unfortunately, though there appear to be several detailed studies currently underway or scheduled for the near future, I've been largely unable to locate anything in the literature that focused specifically on this subject of treatment coordination (i.e., before vs. after, etc.).
However, a superficial review of published (peer reviewed) literature on the subject, as well as anecdotal evidence from sources like this (and other) on-line discussion groups, indicates that the vast majority of 'triple-play' patients are subjected to treatment in the reverse order (i.e., ADT+IMRT+LDR-BT). In fact, the very term "boost" that is often applied to brachytherapy would seem to imply that it is/was intended to 'follow' IMRT (not precede it). And if one digs even further into published books on the subject, like Dr. Michael Dattoli's text entitled "Brachytherapy and IMRT: A Primer on Seed Implants & IMRT for Informed Patients", you quickly discover two apparent reasons why most practitioners feel that IMRT followed by LDR-BT, is the preferred approach:
1) Conducting the 5-6 week long IMRT sessions PRIOR to LDR-BT can essentially sterilize the tissues before the implantation of seeds, thereby minimizing the prospects of cancerous prostate cells being released into the general bloodstream by needles used in the implantation process (an argument I've often seen used against biopsies in related discussions).
2) Since the radioactive emissions from the Pd-103 seeds last for several months (not days or weeks), conducting the IMRT sessions PRIOR to LDR-BT reduces the potential for adverse side effects from excess radiation to non-target tissues (e.g., seminal vesicles, bladder and/or rectum), by way of real-time combined (or overlapping) 'double-dosing', which is difficult to regulate or define in pre-planning stages.
Needless to say, I've asked my RO why he seems to prefer doing LDR-BT before IMRT, rather than the more common (IMRT then LDR-BT) approach, but unfortunately, his answer fell a bit short for me. All he said was . . . "we'll be happy to rearrange the treatment sequence if there are any personal or family scheduling issues." In other words, he didn't offer any technical or scientific rationale for either approach.
I hate to second guess the professionals or to question authority, but at this point, I'm inclined to request a reversal of treatment sequence, based upon everything I've learned and discussed here, but before I do so, I thought I'd
open-up the topic for discussion here on the forum, in hopes of gaining some added perspective(s). Basically, I don't want to seem unreasonable in making such a request, so any additional information or opinions that I can gain on the subject, will help to insure me (and him), that such a request has merit.
Thanks for listening!
Age at Dx: 65 (now 66)
Diagnosis (1/2018): High-Risk PCa
PSA (4/2017): 15
Biopsy (1/2018): 7/12 cores '+' (5-65%)
GS-9 (Initial): 4+5=9, GS-8 (2nd Opinion): 4+4=8
PSA (3/2018) post-biopsy: 43
CT, Bone & PET Scans: No mets
3T-MRI: Nodule r-base (no lymph, but r-seminal vesicle involvement)
PSA (6/12/18): 69
PSA (6/24/18): 34
PSA (7/15/18): 12
Lupron (90-day): 7/17/18
Post Edited (Balladeer) : 7/22/2018 4:27:24 PM (GMT-6)