What Tx options after resistance to Xtandi?

[Tokyoite]

Hi,

My dad (74yo) has developed resistance to Xtandi after 1year of success. now his PSA is 11 and his Dr is suggesting to just continue on Xtandi, and wait until there are symptoms to start chemo (for now he is chemo naive and never had abiraterone)

anyone had good outcomes from some Tx after Xtandi resistance that is not chemo?

Im thinking provenge (sipuleucel-t) or one of the PARP inhibitors (if BRCA+) as alternatives before chemo, but seems they re indicated after having tried chemo, my understanding is that this order maybe due to high cost and not nevessarily patient outcome, so maybe if cost wasnt an issue is it worth pushing for provenge?

Thank you very much

[Tall_Allen]

Why wait for chemo? It's definitely his best option. The survival benefit and side effects of treatment get worse the longer he waits.Too many men wait too long to get much benefit from it. He probably imagines it is worse than it is based on others experience with other chemos for other kinds of cancer.

[Tokyoite in reply to Tall_Allen]

its actually his doctor who is holding off for chemo saying that since my father has no symptoms and gd quality of life, its unecessary to “break” him given his old age with chemo, until it’s absolutely necessary.. so he will check in 3 months on his situation and PSA, he says “I treat a patient with symptoms and not a PSA number”, thats why i wanted to have different opinions on what could be done.

Thank you for your time

[Tall_Allen in reply to Tokyoite]

I'm glad my doctor treated me before I had symptoms.

[EdBar in reply to Tall_Allen]

Just curious Allen were you treated with chemo?

Ed

[Doseydoe]

I would not wait for symptoms. If my PSA got up to 11, I would want to find out what's causing the rise. I would discuss various scan options with my Oncologist. If you wait, then what ever is causing the rise in PSA has a chance to grow and cause real problems. Identify the problem, then decide on a treatment plan, 🤔DD.

[Dalph87]

Don't wait and do chemo immediately, it might even add a chance of Xtandi working again soon after.

Best wishes.

[Hidden]

I agree with those saying not to wait for chemotherapy. The problem with waiting until symptoms show up is the cancer could have progressed significantly making it harder to control. Plus there is the issue of his fitness for chemotherapy. I understand that many people avoid chemotherapy as long as possible, but in the process they are missing out on valuable treatment that is tolerable for most. I went through it myself and would do it again.

[tango65]

He could get a PSMA PET/CT and see if the location of the cancer could be detected. If there are visible metastases, he could consider to get Lu 177 PSMA treatment abroad if it is financially possible.

Lu 177 PSMA treatment has few side effects unless the patients has a lot of bone metastases or bone marrow infiltration. It is not the standard of care (the SOC will be doing cabazitaxel and then erleada or abiraterone along with provenge). There are not RCL indicating Lu 177 PSMA could improve overall survival, but as I said this treatment is usually well tolerated and could give him sometime without other treatments except ADT.

Other possibility is to apply to the trials with modified niclosamide which could make the cancer to respond to enzalutamide again.

clinicaltrials.gov/ct2/resu...

They had some positive results in small previous trials

health.ucdavis.edu/synthesi...

[NevsMates]

More cancer is surely never better than less cancer. I would go for chemo now.

Good luck.

Lut 177 requires you to have two different scans or you risk just wasting money.

Gallium 68 PSMA PET CT and not sure of the other one, something like Flourine 18 FDG PET CT.

In any case if any metastases show on the FDG scan that are not on the Gallium 68 PSMA

Lut 177 probably will not work.

Lut177 attaches to the PSMA. Others will be aware of the finer details.

[EdBar]

That’s a tough call, I had chemo 6 years ago when I was 55 and it was pretty rough, I still have some residual effects from it. So far it seems to have enhanced my overall treatment and I’m doing well, but for me it was no walk in the park. Add to that the fact that we’re in the midst of a pandemic and that it will very likely wipe out your immune system and that adds another element to the mix.

In the end it’s up to your dad whether he’s willing to endure chemo, it may buy him more time and be well worth it. But if I was 74 I’d be looking at other options too before opting for chemo.

Ed