Is my PCa becoming castrate resistant?

[dac500]

I am on ADT break. Three months ago my T was less than 20 and my psa was 0.104. Now my psa has increased to 0.188 but T is still at castrate level with T=28. Is my cancer becoming castrate resistant? Should I start more Aggressive treatment soon?

[Magnus1964]

As far as I can tell you have not been on zytiga, xtandi or any of the newer ADT drugs. So no you are not castrate resist. Also, I see you have had your questions on intermittent ADT. I am not a fan of "vacations" from drugs. It only gives new cancer cell lines to become resistant.

[Shooter1]

Not yet. Off adt PSA often starts to climb. Just showing that adt had been working. Get back on it and maybe add second line treatment. (abi or enzo). Life Is Good and you have lots to live..

[tango65]

If the PSA is going up when the testosterone is less than 50 , the cancer is castration resistant.

The optimal value of testosterone for treatment of metastatic cancer seems to be below 20.

It is possible the increase in your PSA happened because the minimal increase in your testosterone. It happened to me. My PSA started to increase when the testosterone got to 30. A shot of Firmagon got the testosterone back to undetectable and the PSA went down and remained down and stable for more than 1 year.

If you go back on ADT and the PSA continues to increase when the testosterone is less than 20, then you will be sure the cancer is castration resistant.

If that is the case request a bone scan and a CT scan and if there are not mets, you will qualify for darolutamide which is effective in controlling the cancer for a while and it has less side effects than other anti androgen drugs.

[Tall_Allen]

You are using too many decimal points and you need at least 3 measurements a month apart to calculate PSADT. There are always resistant cells. Usually iADT should end when PSA goes above 2.0.

[dac500 in reply to Tall_Allen]

I am having another PSA and Testosterone text six weeks from now.

[tennis8285 in reply to Tall_Allen]

I am somewhat confused as when to take action when on ADT vacation. To set the stage, I am on Lupron and Keytruda and psa has been undetectable for 17 months. Initial scans showed lymph nodes and bladder neck invaded with pc two months after prostatectomy done two years ago. Gleason score of 10.

I plan to have my last Lupron shot next week (completes two year treatment), but Keytruda to continue till April, 2022. First of all, after treatment stops, how often should I get psa checked? Three months seems like a long time with Gleason score of 10. Also, should I be getting the super sensitive psa test which I assume goes to three decimal points? Based on some previous posts, it seems that no action is warranted until psa rises to a certain point (0.2). Is that correct or is the rate of rise also relevant? Although there will be not be an absolute correct answer, how much of a gamble is it for me to take an ADT vacation? By then, I should have (hopefully) psa undetectable for 22 months.

[Tall_Allen in reply to tennis8285]

Why are you getting Keytruda? Are you MSI-hi/dMMR?

[tennis8285 in reply to Tall_Allen]

Yes! In fact, a while back on another post, you mentioned that was the reason the keytruda was working so well for me.

[Tall_Allen in reply to tennis8285]

I thought so, but it wasn't in your profile (a VERY important fact) so I was afraid I misremembered.

Anyway, Keytruda is effective for MSI-hi/dMMR across all different kinds of cancers. From what I've read, it keeps working for a long time, and doesn't seem to require adjuvant therapy (e.g., ADT). So you are fine through April 2022 with no further tests. The question is - after that, will your immune system take over without it, as it's supposed to. 3 month checks seems prudent starting in April, maybe less frequent as time progresses. There is no point to having ultrasensitive tests.

[tennis8285 in reply to Tall_Allen]

Thanks. I value your opinion. If I stop the Lupron after this upcoming final shot, I plan to get PSA test done monthly after the Keytruda treatment ends, even if I have to pay for it.The reason is because of how aggressive the few remaining cells after surgery behaved. The surgeon, the second opinion oncologist, and my present oncologist were all surprised at how aggressively this cancer has progressed. Only the Keytruda saved me.

If it wasn’t for my low red blood cell count, I would probably opt to stay on the Lupron after the immunotherapy ends. Thanks again.

[Tall_Allen in reply to tennis8285]

MSI-hi/dMMR is both a curse and a blessing. It is responsible for the aggressiveness of your cancer, but at the same time, it is the only reason Keytruda works so perfectly for you. It is tempting to say you are "lucky" to have it, except that you would be much luckier not to have it at all.

You should do whatever makes you less anxious. However, in my experience, more frequent PSA tests (and especially with more decimal points) only serve to increase anxiety. The discussion you may want to have is what will you do if your PSA increases and at what point you would take that step. My guess is that the only therapy that would help you is to resume Keytruda - and I don't know if there is any value in resuming it sooner rather than later. I don't think there is much data to go on - perhaps talk to an oncologist who has treated other patients with MSI-hi with different cancers.

[tennis8285 in reply to Tall_Allen]

Thanks for the info. By the way, I did update my profile so my relevant medical history is accessible.

[Hidden]

In my very humble opinion, that change in PSA is not anything to be concerned with. Especially over 3 months. Enjoy your break!

Merry Christmas