Why has my PSA declined dramatically since Xtandi failed?

[BillDoc]

Diagnosed in 2006 with prostate cancer which had spread beyond my prostate. Recently, it became apparent the Xtandi I’d been taking for 2 years failed. (Seizures landed me in the hospital for 2 nights). (Before starting Xtandi, I had 3 years on Zytiga). I’ve had 2 PSA tests since quitting Xtandi. Results of the 1st lab: my PSA dropped from 46 to 33. 2nd lab last week: PSA down to 17. Also, I’ve added back 14 of the 55 pounds I lost in the last 5 months. Now, the only cancer meds I’m taking are Lupron and prednisone. Any thoughts on what accounts for my huge drop in PSA and reversing weight loss and actually adding back some lost pounds?

[tango65]

You could have an anti androgen withdrawal syndrome (AAWS). There is some info here:

pubmed.ncbi.nlm.nih.gov/249...

It has also been described for bicalutamide (casodex).

[BillDoc in reply to tango65]

Thank you.

[tango65 in reply to BillDoc]

Best of luck.!!

[LearnAll in reply to tango65]

There is a case report that in a man the bicalutamide withdrawal lasted 8 years and his PSA was undetectable for all these 8 years. Generally, Bicalutamide withdrawal lasts 6 to 8 months.

Ref: Masayuki Sano et al. Cancer Hospital Institute, Tokyo,Japan. May26,2016.

[BillDoc in reply to LearnAll]

Thank you.

[Tall_Allen]

Why are you still taking prednisone?

There is a "Xtandi Withdrawal Syndrome" that can occur in some patients when the androgen receptor learns how to use Xtandi to activate itself. If that happens, stopping Xtandi makes the PSA decrease.

bjui-journals.onlinelibrary...

[BillDoc in reply to Tall_Allen]

Oncologist says my adrenal glands are shot and I should continue taking prednisone everyday no matter what meds I’m taking or even if I’m on no meds.

[Tall_Allen in reply to BillDoc]

oic. Makes sense.

[LearnAll]

BillDoc,

its a good idea to gradually taper off your prednisone so your adrenal glands get a chance to regain its functioning. Longer you suppress adrenals ,harder it gets for them to recover their natural function. Discuss tapering schedule with your doctor.

[BillDoc in reply to LearnAll]

Thank you.

[Olivia007]

That’s great news

[Patrick-Turner]

I was diagnosed 2009, and had Zytiga for 8 months 2017-2018 while it worked, but Psa just went up after.

I'm on Xtandi now after chemo failed and Lu177 gave big drop in Psa, but only for 18 months.

I may also have adrenal gland unable to make its equivalent natural equivalent steroid to prednisone from a bottle. But I am not taking pred now, and not noticing anything bad.

I must ask my doc about this next time I see him soon. During Zytiga time I only needed to take two 5mG tabs of pred daily 12 hours apart. I once stopped totally and once took 25mg daily after Zytiga time and I felt no different.

But I cycle 200km+ per week, speed is good for my age at 73.

But what do scans of your Pca show to you and doctors?

Patrick Turner.

[j-o-h-n]

Greetings BillDoc...... Yes it would be nice to bill our doctors for waiting time... Anyway Doc would you be kind enough to give us more of your bio data: Age? Location? Treatment center(s)? Gleason score? Doctor's name(s)? Thank You!!! All info is voluntary but it helps us help you and is helps ua too.

Good Luck, Good Health and Good Humor.

j-o-h-n Monday 09/14/2020 6:31

[Olivia007]

I have a quick question how do u know xtandi failed and u stopped it after 2 years of being on it if your PSA is getting lower? Thank u

[BillDoc]

Before quitting Xtandi, my PSA was rising. It was 11 when I started on Xtandi and about 46 when I quit. The real clincher were the seizures.