When studies refer to adjuvant ADT with radiation are they counting the length of time from the start of RT or the end of the RT course ?
And as previously questioned I didn’t quite get the answer I was looking for. In research when they refer to 6, 12, 18, 24 or 36 months of ADT, are they counting calendar months or 12 weeks as three months. For example each 3 month Zoladex implant is 12 weeks not 3 calendar months.
Obviously at 6 months the difference is minimal but when you get to 18-36 the actual time difference increases.
I can’t find this detailed in any of the methods sections of the papers I have looked at.
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SimMartin
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Clinical trials begin timing of adjuvant hormone therapy from when it is first used, typically 2 months before radiation is started. Clinical trials end when their endpoint is reached.
Surely that is neo adjuvant (prior to RT treatment) whereas adjuvant is with/after RT treatment- a paper published in the Lancet suggests that it is the duration of Adjuvant HT that is important not the length of neo adjuvant or have I misread it ?
I can see why you're confused. "Adjuvant" is used generically to mean ADT that is added to RT, whether it is started before (neoadjuvant), during (concurrent), or after (adjuvant). I am guilty of such loose usage, because doctors and patients usually understand the start date is 2 months before RT.
They avoid the term altogether in this clinical trial for example:
"Patients undergo RT over 2-11 weeks and receive ADT (consisting of either leuprolide, goserelin, triptorelin, degarelix, buserelin or histrelin and bicalutamide or flutamide) for 24 months in the absence of disease progression or unacceptable toxicity."
Kishan's study looked at several clinical trials where neoadjuvant ADT was used in all the trials. He found that whether 3-4 months or 6-9 months were used neoadjuvantly did not make a difference in outcomes. All the clinical trials he looked at had about 2 months of concurrent use too. His study highlights the importance of longer duration of ADT afterwards, but in no way says that neoadjuvant and concurrent use can be eliminated.
Thanks for explaining that - I am just trying to work out if I can get away with 18 months adjuvant, if having started being adjuvant in August 2022 with 2.5 months of 150 daily bicalutimide (longer than most as they were unsure of my tolerance to Zoladex due to my polio) but then I decided to opt for the Zoladex prior to RT for another 6 weeks - and then have remained on it - despite the oncologist being wary and saying I could stop at 6 months.
I’m trying to judge when to stop for myself … can I trust 18 months adjuvant that’s my decision to make !
Kishan did another study where he found that the optimum duration of ADT for high risk patients getting EBRT is 26 months. That is largely based on the DART 01.05 GICOR trial on which they gave 28 months of ADT (2 months neoadjuvant, 2 months concurrent, and 24 months adjuvant). Unfortunately for you, the study you linked shows that the extra 2 months of neoadjuvant ADT you had doesn't count. You still require 24 months of adjuvant ADT.
There are ongoing clinical trials that will someday prove whether only 12 months of ADT may be all that's needed for low genomic risk patients, or that intensifying ADT with a second line hormonal agent may be beneficial for higher risk patients.
Thanks - seems all round the best for me is as close to SOC of 24 months as I can tolerate. Might only make 18 months if I go with the oncologists advice or is it fears of SE for me, which they tell me get worse after 12 months - ?
that is not what the advice on administering by the manufacturer states : to quote for the ‘3 months injection:
22.5 mg IM every 12 weeks
So that is actually a 4 week not calendar month regime
Of course for an individual or who administers it, this may not be significant especially if their T is suppressed mostly all the time especially when your on for life.
My issue I want to clarify is research data where treatment with curative intent or attempt to delay or stop biochemical recurrence as long as possible is using terms such as 6,13,18,24 and 36 months - I am thinking there is a vagueness on what is done in each trial, centre of health provider that input in the trials !
So you would count as 22 months adjuvant and 2 months neo adjuvant- so were assuming you had 3 monthly injections- were they strictly every 12 weeks and carried on until a specific date - if 24 months (96 weeks total) or 2 calendar years (104 weeks) ?
Recent research is suggesting that - it is the duration of HT received DURING AND OR AFTER radiation (called adjuvant) NOT the time before starting radiation treatment (called neo adjuvant) that predicts the length of time to biochemical recurrence and death.
they suggest that this is independent of most variables.
So when studies refer to 18 or 24 months of hormonal treatment (ie T blockage) are they:
A) including total time before and after radiation
B) what do they count as 6 or 18 months - ish s that 6x4 weeks or 18 x 4 weeks or is it just a random and may be calendar months or 4 week months
Or am I asking an unanswered question or not being understood?
Sorry I may not be clear what your actual question is but will attempt to answer:
a) Mine included total time before and after radiation. So 2 Years from starting HT. This is for my initial treatment for curative intent which is most likely different than yours. My BCR was evident approx 8 months after stopping HT to see if a cure had occurred.
b) I guess it depends on how your doctor defines a month. Mine was close to calender your Drs may be different. I am sure he will inform you when to stop HT. That said I am not sure it matters that much either way as it would be a few days only.
My oncologist was suggesting I stop after 6 months as she was concerned about the impact on my life as a wheelchair user and night use of ventilator for years as a polio survivor - as there is a chance as localised despite G9 of trying for curative intent I kind of wanted to try at least to carry on - so my oncologist is rather more ambivalent than me so hence me trying to work out what the actual best duration might be - of course it may end up as you after stopping HT with BCR which I’m half prepared for - but thought I’d have a shot at it !
I actually confirmed at some point that psychologically false hope is better than no hope at all. In your case if confined I think you can have good old run of the mill hope. Best of luck to you!
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