I have ealrly stage 4 prostate cancer, have been on lupron for just over 4 months, and enzalutamide Xtandi for just under 4 months. Not enjoying the side effects of 160 mg I reduced my dosage to 80 mg and tolorate it a little better. Every medial professional and non medical professional cautions me againstthe reduction but for atleast the last month my PSA has been holding fast at < 0.05 the same as before when I was taking the full 160 mg dose.
Can anyone explain to me if or why I should not deviate downward from 160 mg?
Thanks,
3Step
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3step
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160 was the maximum tolerated dose used in the clinical trial to get approval. Minimum effective dose can be much lower for many, apparently including you. Many do just as well on 80 mg per day. Just follow your own results.
I am doing this with Bicalutamide at 1/10 the maximum tolerable dose and my latest PSA was 0.005. Documenting this month by month in my Bicalutamide Maneuvers thread.
A PSA decline of more than 50% (PSA50) serving as an end point for a new drug's approval by FDA, is good enough, but if tampered with dosage it is demoted to the state of a mere biomarker. The modern re-invention of good old Catch-22.
The small print on these trial is the cut off is PSA 0.5. For the practitioners such as Dr. Scholz they see the PSA getting down to PSA 0.1 in 4-5 months. There is a gap there. Most doctors will quote the trial results to avoid any lawsuits. Who knows?
Dont mind me. I am just another layman trying to make some sense out of the whole thing. Most times I dont even know the different medicines. 😊
Another thing is PSA 0.1 or <0.1 or whatever is the level which is defined as cure after surgery (and/or radiotherapy?). How is it different if you get there by ADT alone or plus something like chemo etc?
Dont mind me. I am just another layman trying make some sense out of the whole thing. Some times I wonder even the doctors have the same problem? 😀😀😀
<0.1 is the "lack of medical attention" PSA range. They call it other missleading names, so that patients are happy and don't pose questions. In laymen parlance: "Come back when your PSA gets over 0.1, we have no time to spend with/for you at this point".
Surgery and radiation are looked at totally differently. For Radiation it nadar plus 2 to define reoccurrence.
For surgery you need a ULTRASENITIVE PSA test at 6 weeks post surgery. If your PSA is 0.03 or above you're likely to have reoccurrence. If you're PSA is 0.02 or below your unlikely to have reoccurrence.
You MUST get a ULTRASENITIVE PSA test that shows to these levels to know. LabCorp Ultrasenitive PSA goes to 0.006
All of these PSAs are with NOT taking any ADT etc. Just surgery or radiation.
The PSA test of <0.1 is such old technology it tells you nothing. It is just the level at which your doctor begins considering giving you treatment. It by no means means you're undetectable or cured.
You can begin using the cheaper <0.1 PSA test when your PSA rises to over 1.0 or 2.0 if you want. It might all depend on how fast your PSA increases.
So one more thing concerning undetectable. If you stood on a beach with a telescope looking out to sea and saw no ships, you were unable to detect them with that approach.
But now you climb a 100 foot tower use the same telescope look out to sea and see many ships. You detected the ships because you used a better test.
We're the ships not there when you stood on shore, of course not, they were there you just couldn't detect them until you used a better technology, the tower.
The question is that practitioners do achieve PSA <0.1, ie 0.0 something with ADT. What is the difference? 0.1 is used only because there is some debate as to whether going further down has any clinical meaning.
Dont mind me. I am just another layman trying to figure out something. Heck sometimes I do wonder if some of the medicals are too?😀😀😀😀😀
So ADT is expected to bring most people to <0.1 over time. It does so by putting PC to sleep.
It kills some small PC but it isn't a cure and when you stop it or it begins to fail your PSA begins to rise again.
So that 6 week check after surgery is only telling you the state of your cancer if you're not on ADT.
Some hospitals dumb it down a bit for the patients and call the ultrasenitive PSA a "post surgery PSA".
So hospitals don't usually initiate new treatments unless the PSA is =>0.1
Some insurance won't pay for PET scans, or deny PSMA scans if PSA not 1.0 for example.
Hospitals may do lots of PSA tests and a test to <0.1 is cheaper than a untrasensitive PSA. So they save lots of money by using the old cheaper PSA test as well.
And this talk about this real loose definition of "non detectable", does work in the hospital favor. The patient feels that they received good healthcare than if they told them right away your PSA didn't reach a lower enough level shown to really indicate the truest chance of no reoccurrence.
First we are told if you had surgery, that is a cure. The cancer will not recur. Except when it does. Same as any other form of treatment. It seems rather random.
Dont mind me. I am just a layman trying make some sense of the whole thing. Well, some times, it seems the more honest professionals are in the same boat. ☺️
I had high BP when I used Zytiga full dose. My MO counseled me to reduce the dose. In her words "this is not rocket science".
A question: does a 220 lb man need the same drug dose as a 135 lb man?
A note: trials generally find the maximum tolerated dose and then apply it. It is not the minimum effective dose. And it is rare to find a prostate cancer trial that adjusts the dose for the size of the person (volume of blood). I don't know why this practice is common for many health issues but not PCa. But it does help me understand my MO's words.
We all tolerate drugs differently and I for one tolerated Xtandi about as good as you. I went back to Zytiga instead of lowering the dosage on Xtandi. If you go back to full dose they will say its working if your PSA is low and if you stay at a lower dose the same. Are you getting scans because if PSA is just a biomarker regardless of dosage than the only option is to get scans to look for the cancer. My MO seems to be waiting for me to say I have pain before ordering new scans. Maybe he'll say it's time at some point regardless or I can push for them if I feel its time. Doubt I'll get new PSMA so they will just be watching for something to show up on conventional imaging from here out. I was disappointed by the lack of SUVs on my last and only PSMA. In the meantime I feel great and am glad Xtandi is in the rear view mirror.
According to Sartor, 80 mg is just as effective as 160 in his practice. According to my MO, balance out your drugs as you need for your overall health. Her words "this isn't rocket science".
Maybe even better, why not intermittent use? Seems to have much better results - Ask your MO
I began Xtandi at the 160mg level. It brought my PSA down to 0.1 shortly after. However, some of the side effects including rising blood pressure was of major concern. My oncologist lowered my intake to 120, and then to 80 mg daily. PSA levels remain unchanged at 0.1. I have recently changed to zytiga to see if I can avoid some of the worrisome side effects of Xtandi. Best to you and all the warriors on this platform. The medicine that will cure us is coming.
Smash your wrist watch and it will not be an indicator of current time any more. Right? Kill or deactivate all hormone sensitive cancerous cells, expressing PSA, by overdosing hormonal drugs and it will not be a valid indicator of the burden any more. Achieving undetectability gives patients bragging rights but stimulates progression IMO. Establishing a low population equilibrium between new and past cells delays castration resistance, again IMO.
I get sad every time I see a post about someone using ADT or double hormone blockade to keep their PSA undetectable. I know what is coming but try to keep my mouth shut.
I started in Enzalutamide one year ago July at one tablet per day to replace bicalutamide PSA response was good and then December began monthly Lupron injections and bumped up to 80 mg PSA dropped to 0.1 cut back to one pill per day in March PSA continue to decline and it’s been steady since then that less than 0.0 1 PSMA scan this week showed no evidence of disease. prior scans had shown bone and lymph metastases. Most recent previous scan was in February
MO describes this as a “complete response”
He also knows that once we see progression to bone metastases the disease always seems to reoccur
Will complete one full year of the combined blockade around Thanksgiving, and then consider holiday or Enzalutamide alone each person’s response is different because each person’s disease is different. Think of yourself as your own “case control study” in conjunction with your providers to optimize your outcome
My husband began Xtandi full dose in mid-June. Due to intolerable side effects (blurry vision, chest tightness) reduced to 1/2 dose July 8. PSA a month later was 11.32, down from 14.7 on May 3. He began experiencing acute hip pain running down the side of his leg. Xtandi side effect?
Dear friend, the recommended is 4 capsules once a day, however you can take 2 in the morning and 2 at night, you will have better tolerability and you will maintain optimal drug concentrations.
I had the same questions - and decided to moniter this on my PSA decline curve (see my profile). I had a smooth and predictable decline, and 3 month intervals between changes from 80mg to 120mg and back showed no significant effect on the PSA decline curve.
If we assume that a steady PSA decline is due to Xtandi, and is an indication that the tumour burden is getting lighter then I take this as an indication that 80mg is doing as good a job as 120. Some say the PSA is not your cancer (true) but a decline in PSA is logically a sign that the tumour burden is lessening just as an increase in PSA signals the opposite. (standard interpretation)
It also makes sense that when the tumour burden is diminished then you dont need the same quantities of Xtandi in the bloodstream as required to zap a larger tumour burden. So I continue on 80mg per day with the blessing of my oncologist!!
160 mg i MTD, maximum tolerated dose, not minimum effective dose.
For me a dose reduction helped with adverse and intolerable events. After approx. 3 months at 160mg, (Dec 2019 into 2020) MO dropped me to 80mg, coming up on 4 years Xtandi/Lupron combo appears to still be effective. Full dosing info from Xtandi is here --> astellas.us/docs/us/12A005-... Good Luck!
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