Becoming castration resistance or not?

My father diagnosed with APC on dec'17 after turp . His psa was 228

On jan 2018 doctor prescribed Zoladex + calutide

On fabuary 2018 he also prescribed zoladex+calutide

On March 2018 he prescribed only calutide

On April his psa was 0.9

Then he put my father only on calutide

On September his psa was 2.8

Till November 2018 he is only on calutide his psa rise to 11.3

On November'18 doctor prescribed Zoladex+casodex

His psa on November down to 9.56

On December'18 again zoladex+casodex

On January his psa down to 7.81.

My question is this why his psa decreasing slowly as compared to april'18

Is he slowly becoming castration resistant.

Why the response is slow .

[AlanMeyer]

I presume that by "calutide" you mean "bicalutamide", sometimes given under the trade name "Casodex".

I am not knowledgeable enough to give a good answer to your question. However I will say that, for cases of aggressive advanced prostate cancer, which your father presumably has, the new standard of care is to combine a drug like Zoladex with either Zytiga hormone therapy or docetaxel chemotherapy. The Zytiga or docetaxel should be added now, while he still has a decent response to the Zoladex.

I think the doctor should be asked about this and, if necessary, a second opinion should be obtained. I recommend going to one of the teaching and research hospitals for a second opinion such as those listed here:

en.wikipedia.org/wiki/NCI-d...

I wish you the best of luck.

Alan

[AlanMeyer in reply to AlanMeyer]

I see that "calutide" is a drug name used in other countries. It's called "bicalutamide" in the U.S. I didn't realize that you weren't in the U.S. and so your treatment options are different from what I know most about. I apologize for my confusion.

Alan

[Tall_Allen]

Yes - he is castration resistant - his PSA when he was taking Zoladex+calutide was 0.9, and now on the same two drugs, is PSA was 7.8. Sometimes, stopping calutide and continuing with Zoladex will make his PSA go down. Has he had a bone scan/CT? - any metastases?

[Hidden in reply to Tall_Allen]

Yes he has multiple bone Mets.

[Tall_Allen in reply to Hidden]

Is he in India? In the US, he would have several choices: Taxotere, Xofigo, Provenge, Zytiga or Xtandi. But I'm not familiar with what is available there. I think Lu-177-PSMA-617 is available in India.

[Hidden in reply to Tall_Allen]

No I am in Pakistan

[Tall_Allen in reply to Hidden]

I don't know what is available in Pakistan, sorry.

[Hidden]

I don't undertsand why he was taken off Zolodex for a while. It looks to me like that is what made his PSA go up.

Once he got back on Zolodex, it looks like his PSA has only gone down. So I don't see how it can be determined that he is castrate resistant unless I am missing something.

Once the PSA hits the bottom (nadir) and then starts to rise again significantly, then you can say he is castrate resistant.

[curious-mind1]

If his PSA keeps going down 2 months in a row, after the reintroduction of Zoladex, it is probably that he is not yet castrate-resistant, but that resistance may be setting in. It seems like he should continue using Zoladex, but also add additional drugs (docetaxel, or zytiga/xtandi if possible).

Best,

Arthur