You will know if the cancer is castration resistant when your testosterone is below 50. If with a testosterone below 50 (ideally less than 20) your PSA stars to go up or there are imaging studies showing disease progression, the cancer will be considered castration resistant.
If your testosterone continues to go up and the PSA continues to increase with similar speed, the PSA could be between 1.5 and 2 by October/November. You could continue this way and get monthly PSA instead of every 3 months.
You could discuss your situation with your MO and talk about possible treatment with zytiga, apalutamide, enzalutamide or docetaxel , drugs approved for the treatment of hormone sensitive metastatic PC.
The PSA is increasing rapidly. I f you round the numbers, it when from 0.1 to 0.4 in 3 months. Your PSA could be around 1.5-2 or higher by October-November. The PSA could increase more rapidly as the tumor load and the testosterone keep going up.
It is difficult to guess what is going to happen. In my personal experience my PSA went from doubling every 4 months to doubling every one month as the time progressed. Metastases get larger and they start putting more PSA etc. You should talk with your MO about this situation.
My fear about intermittent ADT has always been that the testosterone rises enough to feed the cancer before it gets to the point where you feel any benefit.
Do you feel like that is what has happened here or did you have a benefit before the PSA started rising?
My PSA started rising within nine months after the last Lupron shot. And Testosterone increased beyond castration level after six months from the last Lupron shot. So, I had virtually no time to feel any benefit from my ADT break. Even now I have hot flushes. Only reason I agreed to have a break is to reduce other risks like cardiovascular or diabetes as mentioned by my MO. But if my Testosterone remains low around 150 or so, I believe that benefit of lesser risk is not there as well.
Although it needs to be pointed that 'comparisons' may be misleading, I will offer you this commentary.
I might be ahead of you, somewhat. I am on an ADT vacation and have been for over 2 years.
My vacation has come to an end - although the next 'round' of treatment has yet to be determined. That will happen in the next few weeks - which will include some form of systemic treatment - likely some form of ADT and more scans etc ....
During my vacation, I was undetectable for about 16 months. My 'T' recovered gradually, to land within normal limits. My 'T' went above castrate levels within 6 months - but it was slow and gradual until about 6 months ago.
Within the last 12 months, my PSA went from 0 to 3.2 - with the largest jumps (doubling) around 3 months. Last 2 readings - 1.7, 3.2.
I was under no form of treatment. I was advised that some PSA should be expected because I still had mine. The key factor was - how much - preferably staying below 2.0.
Ideally, 1.0 (or lower) would be the target because my primary treatment was RT and ADT.
My Dx was T3b (node positive), G9, PSA > 300 - May of 2017. I do not believe I am castrate resistant (yet).
So, here's my 'read' on your current state - but I'm no doctor ....
You probably aren't castrate resistant (yet) - you need to so a bit more research / reading to understand the potential progression of the disease.
You appear to have had a BCR - you still have some cancerous activity happening within - they didn't get it all the first time - for whatever reason(s).
I believe you need to take some action - get some face time with an MO to determine what is next / best for you.
This doesn't mean it's the end - don't panic !
I've gone 3 1/2 yrs so far - feeling well - my strength came back - played golf at least 3 times a week.
I'm not happy about the turn of events, but it could be MUCH worse - there's still time to engage the beast - the future is unknown, but I would like to think that I have more than a few years to go AND maybe - another vacation down the road ?
Your latest T is still below Morgentaler's saturation point. You should expect the PSA to rise a bit before it settles down. If you restart ADT now, you will not know the true PSADT IMO.
You ask:
"Is there any indication of my cancer becoming hormone-resistant?"
"becoming"? It cannot become resistant to ADT while you are not on ADT - IMO.
It's easy to become unnerved by PSA increases during the off-phase of IADT.
Typically, a man on an ADT vacation will follow an algorithm for determining its end. It's not Russian roulette. You should ask your doctor for the algorithm. You might be able to squeeze a bit more out of this vacation.
Content on HealthUnlocked does not replace the relationship between you and doctors or other healthcare professionals nor the advice you receive from them.
Never delay seeking advice or dialling emergency services because of something that you have read on HealthUnlocked.