Zytiga &Dexamethasone or what?

Dear all

My dad started taking Zytiga with Prednisone 2.5 months ago and he would take PSA test (and maybe other test) in next 2 weeks as per his doctor’s prescription. We are a little bit worried if Zytiga & Prednisone don’t work for him because he feels passing urine is more difficult than previously. Therefore, we are thinking what next step should be and would like to get your sharing / advice.

1. Do you know any case that Zytiga with Prednisone initially does not work for that person, but Zytiga with Dexamethasone works for him? Some people shared that when Zytiga with Prednisone worked at first and when its effectiveness reduced, they took Zytiga with Dexamethasone. However, in my question, the situation is Zytiga with Prednisone did not work at the beginning.

2. Do you know any case that Zytiga did not work for that person then he takes Xtandi and it works? Some people shared that they took chemo before moving to Xtandi from Zytiga. But in these cases, Zytiga did work for them. If Zytiga did not work at first, should my dad move directly to Xtandi or re-take Docetaxel? He finished 8 rounds of Docetaxel last November. Cabazitaxel is not available in my country.

3. Do you know anyone who is under ADT treatment but has BPH?

Thank you for your sharing and advice

[Hidden]

Do you have any indications that Zytiga is not working at this time?

[Hidden in reply to Hidden]

Thank you for your reply.

§ After taking Zytiga for 1 month, my dad took PSA test and it increased from 3.52 to 5.55. To avoid any unnecessary worries, he did not take PSA test after 2 months but wait for the test in month 3 as per his doctor’s prescription.

§ Recently, he has urinary retention

§ Yesterday he got the ultrasound check and the urologist said light BPH, the prostate is about 27gr and it was 14gr after 6 rounds of chemo in Oct 2020. We think it’s unnormal since he is taking cancer treatment and it’s the reason for my 3rd question in the initial post.

Whether the above points can be considered as indicators of recurrence? We have limited options in my country which are Docetaxel and Zytiga. Cbazitaxel is unavailable, Xtandi is available in the market but not in hospitals even thought it is mentioned in clinical protocol.

It’s lucky for us to join this forum where we can learn a lot from participants’ sharing.

Thank you and Stay safe

[Hidden in reply to Hidden]

Smart to wait to check the PSA. My doctor told me that we shouldn't check PSA too soon after treatment change. We can have too much anxiety doing what I would call "chasing the PSA". The big challenge is to manage our anxiety while at the same time fighting the cancer with everything available. His PSA is still low and it's important to keep that in mind.

You might not be able to choose the sequence of drugs which is currently considered to be best because of limitations in your country. So for example, he can't get the second-line chemotherapy Cabazitaxel, but he might be able to retry Docetaxel chemotherapy if it was effective the first time.

The cancer often mutates in ways that eventually make drugs such as Zytiga ineffective but chemotherapy will still work with those mutations. After that he might be able to come back to Zytiga and get more time out of that.

Is genetic testing available in your country? He might have a mutation that has a targeted treatment such as BRCA or ATM. Something to ask about.

Wishing you the best.

[Hidden in reply to Hidden]

Thank your very much for advice. Genetic test ist not available in my country

[Tall_Allen]

1. Until you get the PSA or scan you have no idea that Zytiga is not working. You are creating your own anxiety. You will know when you know, and take it from there.

2. That would be unusual.

3. If he has urinary retention, it may be due to blood clots caused by his cancer. Talk to his urologist.

[Hidden in reply to Tall_Allen]

Thank you for your advice!

It’s hard to not nervous when treatment options in my country are limited and my dad has some symptoms as shared in the post above for Grey57. I am not clear what you mean when saying “That would be unusual”. Do you mean point 3 in my initial post? My dad told the oncologist, but he had no comment or action. Yesterday he met the urologist and she said he had BPH.

Thank you and Stay safe

[Tall_Allen in reply to Hidden]

I'm sorry- yes I meant #3. It is almost impossible to have BPH while on hormone therapy. Hormone therapy is how BPH is treated - it shrinks the prostate. How big is his prostate?

[Hidden in reply to Tall_Allen]

27gr, it was 14gr after 6 rounds of chemo in Oct 2020. I have written detail onreplying for Grey57

[Tall_Allen in reply to Hidden]

That's what I would expect after ADT and chemo. So how can he have BPH with such a small prostate? It sounds like his urologist was mistaken.

[Hidden in reply to Tall_Allen]

Is it normal that the prostate increases from 14gr to 27gr in 7 months?

[Tall_Allen in reply to Hidden]

You mean, normal with cancer? Yes.

[Hidden in reply to Tall_Allen]

Thank you for response. I mean normal in condition of pc treatment (zytiga after chemo). So is it not a indication of progression of PC or zytiga not work?

[Tall_Allen in reply to Hidden]

Yes, it is an indication of progression.If it increased while on Zytiga for those 7 months, it isn't working.

[Pwjpp55]

Hi: You didn't provide much information as to you father's disease progression, however, I got 3 good years out of Zytiga and prednisone. Perhaps you should get the 3 month PSA to see how things stand.

Here's wishing you and your father the best of luck!

[Hidden in reply to Pwjpp55]

Thank you for your sharing and wish you all the best!