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An engineer's Bicalutamide maneuvers

Justfor_ profile image
57 Replies

My goal is to find the minimum Bicalutamide dose that will keep my PSA relatively low until this 4th Covid wave passes and can proceed with my next treatment.

This post is a bit mathy, the bottom line of which is that the data summarized in the "Pharmacology of Bicalutamide" chapter of wikipedia were validated in my case. (en.wikipedia.org/wiki/Pharm...

Ground information before proceeding:

a) The reduction % of PSA, or alternatively the residual % after reduction, is dose related when the plasma steady state concentration has been reached.

b) Plasma steady state concentration is the condition where the daily/weekly Bicalutamide intake equates the elimination due to its decay in the blood. It goes without saying that the period for reaching steady state is related to Bicalutamide's half-life.

c) Interestingly enough, the plasma elimination half-life is dose dependent within the range of 5.6 to 7.5 days according to one study, or a uniform value of 5.8-5.9 days in others including a mention in a FDA registered document. This translates to 45 days (-2/+12) for reaching 99.5% of steady state for doses ranging from 5 to 80 mg/day. The following table was derived from the first study [180].

Dose / Half-life / 99.5% concentration

(mg/day) / (days) / (days)

5 / 7.4 / 56

10 / 6.4 /49

15 /5.8 / 44

20 / 7.3 / 55

30 / 7.5 / 57

50 / 6.0 / 46

80 / 5.6 / 43

d) The residual PSA (%) was approximated by a function, as in the graph on top, in order to make possible interpolation of in-between dose values.

My experiment until now:

1) Started at PSA 0.17 with 50 mg/day for 10 days. PSA went down to 0.09.

The equivalent steady-state dose from a concentration point of view was 27 mg/day, while that from the PSA decline point of view 5.0 mg/day.

2) Lowered the dose to 4x50 mg pills per week for the following 11 days and the PSA went down to 0.06.

The equivalent steady-state dose from a concentration point of view was 21.5 mg/day, while that from the PSA decline point of view 19.0 mg/day. Convergence between the two was noticed.

3) For the next 16 days I slashed the dose into half splitting two pills, i.e. 4x25 mg per week. The PSA remained at 0.06.

The equivalent steady-state dose from a concentration point of view was 20.0 mg/day, while that from the PSA decline point of view 19.5 mg/day. Convergence was strengthened further.

4) Next, will continue with the 4x25 mg/week dose to see how it goes. My current concentration is above the steady state equivalent of 14 mg/day dose, so PSA may rise. The interesting thing is what will be the doubling time of such a rise. There is this "huge" rounding error of 0.06 that can mask any upward or downward PSA undergoing movement. Will report here and then.

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Justfor_
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j-o-h-n profile image
j-o-h-n

Ever feel like your watching two ghosts making love in a snow storm? So do I, many times...

Good Luck, Good Health and Good Humor.

j-o-h-n Friday 12/17/2021 2:48 PM EST

Stoneartist profile image
Stoneartist

Nice work. I am trying to do the same with Xtandi. The maths indicate that standard 160mg dose is OK to build up to steady state - and logic suggests that steady state can be maintained thereafter by lower doses. But I am wondering if there is some resistance factor that should enter the equation which regulates the rate of uptake versus the existing saturation. Havnt found enough data to do this precisely yet.

Justfor_ profile image
Justfor_ in reply to Stoneartist

My algorithm, implemented by the aid of an excel sheet, is to take on a day by day basis the sum of any newly added pharmaceutical quantity (for some days this may be null) and the already flowing within the plasma one and calculate one day's decay which it is carried over as the next day's initial condition. It is possible, like you suspect, that some resistance factor can build up with time, but this can be compensated by making the half-life shorter. There is no such data available that I know of. Only frequent PSA measurements can reveal if this is actually the case or not.

Stoneartist profile image
Stoneartist in reply to Justfor_

Yes - my excel sheet does the same as yours, but I dont think the Norwegian healthcare authorities will back me in making much more frequent PSA tests

🤔

Justfor_ profile image
Justfor_ in reply to Stoneartist

Here is the same, healthcare is ok with testing every 3 months, the rest are out of pocket, but not expensive (around 15 Euros). I use two labs in alternation, so to be able to spot any inconsistency.

in reply to Justfor_

You're lucky. Here in the U.S. I pay $6 for a monthly PSA test covered by my insurance, and for the 3 others I get each month I pay $38 for each. But $125 a month for weekly PSA testing doesn't seem bad. I can easily spend as much taking the wife to a nice dinner.

Stoneartist profile image
Stoneartist

WOW - I never thought of that. I can now get a higher frequency of PSA test done locally - this will be interesting - thanks for the input - and happy Christmas

Justfor_ profile image
Justfor_ in reply to Stoneartist

Happy Christmas to you as well.

Justfor_ profile image
Justfor_

Update: 34 days later my PSA declined to 0.04 from 0.06.

It was a bit of a pleasant surprise as my self-derived model predicted a 0.06 -0.07.

That because by gradually reducing the weekly dose I am approaching the steady state Bicalutamide concentration from above, hence declining. The model estimates the residual PSA from the current (declining) concentration, so some PSA increase seemed reasonable.

It seems that my model needs revision. I also have to decide by how much should I reduce the weekly dose, now at 25x4 mg/week, in order to keep my PSA around 0.05.

Justfor_ profile image
Justfor_

Update: 27 days later my PSA rose from 0.04 to 0.05 (different labs).

Since latest update I have halved the dose into two, or 2x25mg/week.

For this, I split a 50mg pill into two and take each half on Mondays and Fridays.

As I wrote elsewhere, during this period I tried to lower the Tamoxifen to 4x10mg/week.

Doing so, my breasts felt sensitive so I went back to a daily dose and this did the trick.

I am now within my initial target, i.e. 0.05-0.06 and will continue with 2x25mg/week.

From past observations I am aware that today's lab reports a tiny bit higher than that of the previous update. Consequently, I may have reached the sought equilibrium, but there will be a better insight after my next PSA test.

Justfor_ profile image
Justfor_

March 2022 Update:

Since the previous update I have been taking 2x25 mg/week as before (one 50 mg pill split in two. The Bicalutamide blood concentration has long ago reached its steady state . Today's PSA was 0.05 like the previous one measured by the other lab. Today's lab had reported a 0.04 two months ago, but the Bicalutamide concentration at that time was 225% higher. My initial target to maintain a PSA of 0.05-0.06 according to some "Evolution dynamics" (thank you Nal) hypothesis, seems accomplished. Will keep taking current dose and monitoring results.

CAMPSOUPS profile image
CAMPSOUPS

Any chance you could give us a bio. Even just the basics. Gleason, PSA, metastases, etc. at dx.Initial treatment if any.

Thanks.

Justfor_ profile image
Justfor_ in reply to CAMPSOUPS

Surely.

12/ 2018: PSA=7.20, free/total=6.7%.

01/2019: mpMRI -> PIRADS 5, min ADC=4.6.

02/2019: TRUS biopsy -> 6 out of 20 cores positive (2+2+2=6 @ left + right + suspected areas), GS 4+4=8.

04/2019: PSA=7.66.

05/2019: RALP + frozen sections -> GS=4+5, unilateral SVI, pT3b, pN0 (0/20), R0 (gland contained).

06 - 12/ 2019: PSA=0.02.

02/2020 to 11/2021: PSA=0.03 to 0.17, PSADT=~9.5 months.

11/2021: Bicalutamide start.

CAMPSOUPS profile image
CAMPSOUPS in reply to Justfor_

Thanks!

Justfor_ profile image
Justfor_

April 2022 Update

Six weeks after my latest draw my PSA remains stable at 0.05.

It seems that my feeble Bicalutamide dose of one 50 mg/week (25 mg on Mondays +25 mg on Fridays) has established an equilibrium. Yet, I am a bit undecided. The original plan was to have a PSMA PET/CT during summer when the pandemic deeps to its lowest. It is also desirable to have a PSA greater than 0.1 at the time of scanning for increased detectability. If I stop Bicalumatide now, it will take me one month to clean out and according to my prior PSADT ~9 months to double from 0.05 to 0.1, which brings me back the forecasted next peak of the pandemic. In my shoes, what would you choose?

a) Keep it as long as it works.

b) Stop it in September and get scanned sometime in spring-summer 2023.

c) Get scanned around my 3rd RP anniversary (late coming May) regardless of PSA value.

You are welcome to cast your vote.

traveller64 profile image
traveller64 in reply to Justfor_

Hi Justfor,I don't think anything will show up on PSMA scan at those low PSA values. I was off of Casodex for 19 months and got a PSMA scan at PSA 1.27. The scan was negative. Anyway I started Casodex 9 days ago (50 mg/day). Today I had a PSA test that showed it dropped from 1.27 to 0.44 just in 9 days. I plan to keep PSA around 0.2 by adjusting the dose of Casodex. Ithink there is no need to lower PSA to almost zero (i.e. 0.03-0.05).

Justfor_ profile image
Justfor_ in reply to traveller64

Excellent. Let's keep updating one another.

Justfor_ profile image
Justfor_ in reply to traveller64

I run your numbers to validate the Bicalutamide dose vs PSA reduction model:

a) 9 days @ 50 mg/day is equivalent to a steady state serum concentration of 24.6 mg/day (mean half time of 7.84 days assumed).

b) According to the graph depicted on the top of this thread, 24.6 mg/day can reduce the PSA to 31% of its initial value.

c) 1.27 x 0.31 = 0.39, not very distant from the 0.44 that was measured.

Justfor_ profile image
Justfor_

Update, May 22

PSA, fourth month now, stable at 0.05.

Endogenous Testosterone skyrocketed to 3755!!!

Inflammation worsened. CRP and NLR both went up.

Justfor_ profile image
Justfor_

An experiment within another experiment.

My bottle of Curcumin capsules, very conveniently, became empty in sync with my latest PSA test. I decided to abstain from opening a new one during this month in order to test whether it affects or not the PSA.. Having stabilized my PSA to 0.05 for 4 months now, a future increase to 0.06 will reasonably be attributed to the lack of Curcumin. Regardles, I will start again Curcumin next month. If it backs off to 0.05 again than this will constitute tangible evidence that Curcumin lowers PSA. Synergy with Bicalutamide or test masking, this is another story. Will report results.

Justfor_ profile image
Justfor_

No surprises update July 2022

Five weeks post my previous test, PSA remains stable @ 0.05.

As previously noted, this time I also wanted to check the influence of Curcumin on PSA.

For this reason I refrained from taking it all this time.

As of today I started taking it again.

The first leg of my "bracketed" experiment, i.e. ON-OFF-ON with Curcumin, suggests that the purported PSA lowering/masking effect is most probably a red herring.

My next PSA test will be definitive regarding this.

PSA vs Bicalutamide concentration
Justfor_ profile image
Justfor_

August 2022 update.

In my previous blood tests there was a substantial discrepancy in totalT between labA and labB. For a majority vote decision, this time, I used labC. Well, I got my answers regarding totalT but there was a discrepancy with PSA. LabC reports PSA to 3 decimal places, in this case 0.036 came back. The other two labs have been concordant with 0.05 for some months now. Just after the previous test I have restarted taking Curcumin, so there is a possible element there, although when I stopped it for more then a month PSA didn't rise. Plan now is to keep things as usual and in case next test (beginning of Oct.) using labA or labB prints the 0.04, then readjust the Bicalutamide dose.

Justfor_ profile image
Justfor_

I reviewed my supplements list for the period between the latest two PSA tests (0.05 -> 0.036) to notice that shortly after the 0.05 I added Glucosamine HCL (without Chondroitin). Among others, there are mentions that: "We and other investigators also have demonstrated the ability of GS to induce apoptosis in human cancer cells, such as prostate (DU145)...." spandidos-publications.com/...

It is the first time I am trying this supplement and it surely has attracted my attention now. First things first, I will have to verify that a genuine PSA reduction has occurred. In the past labC has been in very close agreement with labA.

Justfor_ profile image
Justfor_

October 2022 update

This time the PSA test was carried out by one of the two labs that I usually interleave and they report to the second decimal digit. The result was 0.03 which after the previous 0.036 can indicate a declining trend. Since the first days of September last I have stopped taking Curcumin, yet continued taking Glucosamine HCL (without Chondroitin). Current PSA decline can be possibly attributed to the latter in an actual or placebo induced way. Alternatively, PCa cells got lazy and went for a nap. I will try to solve this dilemma by halving the Bicalutamide dose and doubling the Glucosamine HCL supplement. In order to get fast enough to the new steady state concentration (that of 25mg/week) I will skip one week of Bicalutamide altogether. Next PSA test in early November which is also the 1st year mark of these maneuvers.

Updated graph
Justfor_ profile image
Justfor_

December 2022 update

Seems that my past dose halving to 25 mg/week was a bad idea that resulted in a rise outside my target range (0.05 +/-0.01). Initial, mid November, PSA reading was 0.074, retested with the other lab 0.09. I hypothesized two possible reasons for the rise:

a) There exists a min Bicalutamide concentration level, bellow which linear control is lost, sort of a hysteresis in control loops.

b) I had reached the point where Bicalutamide stops working, instead reverses and feeds PCa.

To find out what was happening I took for 10 consecutive days the nominal dose (50 mg/day or 350 mg/week) and today tested anew by the lab that reports to two decimal places.

It came back to 0.04 which is kind of very interesting, as when I started this experiment, a year ago, my PSA dropped from 0.17 to 0.09 after ten days of nominal dosage. Now 0.09 to 0.04 during the same time period and dosage indicate that my response to Bicalutamide is as good as it was a year ago when this was started.

Lastly, my calculations indicate that today's Bicalutamide concentration was equivalent to 30 mg/day of steady state supply, consequently, I am halving the dose until next testing.

Justfor_ profile image
Justfor_

Thank you for your kind response. It is the rounding to the second decimal place that doesn't allow exact comparisons between the two drop-rates. Both are approx 50%, give or take. I thought of using the lab that reports to three decimal places, for this reason, but the results of their last test were e-mailed to me the following day after the draw. If the analysis was delayed by one day, then with 3.5 days of half life for PSA, the two (0.074 and 0.09) come very close together. Hence, I opted for verifiable processing interval vs enhanced granularity. I think you would have done similarly.

Justfor_ profile image
Justfor_

January 2023 update:

Thirty five (35) days on half the nominal dose, i.e. 25 mg/day, and I got undetectable (<0.01). Three and a half years after RALP it is my first acquaintance to the less than "<" sign. Well, I must admit that I got lazy during the holidays. Last time I used this dosage, PSA declined from 0.09 to 0.06 within 10 days. I should have had taken the PSA test earlier, so I could re-adjust the dose accordingly and not derail my inner control loop. But, with daughter coming over from abroad for Christmas and the New Year, everything went astray. I understand that most, if not all of you, would brag for getting undetectable. Not I. As I wrote in another thread the stability of the power grid network is based on constantly balancing the power production to the instantaneous demand, also termed as generation to load. Too much production leads to grid collapsing like less does. Our body works the same. Produces Testosterone which, among others, is consumed by the cancerous cells. We have Bicalutamide that can sit in between the two and act as a control valve. Fully open or fully closed valve is anything but optimal. There is a mid setting that will maintain stability quite longer than either of the preceding. An engineer doesn't need any random trial to grasp this. It is just.... elementary.

Conclusion: I am re-adjusting the dose to 3x25 mg/per week and will re-test in a month. For newcomers to this thread my target is 0.05 +/- 0.01.

Justfor_ profile image
Justfor_

February 2023 update:

Forty (40) days at 3x25 mg/week (one and a half tab per week) and <0.01 still holds firm.

Late last week we had an interesting exchange with smurtaw and cujoe (healthunlocked.com/fight-pr... where, in accordance with a graph of my past performance, I guessed/estimated that this PSA count will be in the vicinity of 0.01. Backtesting proved correct. Borrowing a term from the nuclear science, my "critical dosage" is a bit bellow 50 mg/week. I am now considering halving the dosage on a bi-weekly schedule, i.e. Mondays and Fridays on week#1 and Wednesdays on week#2. This is equivalent of 37.5 mg/week. Hoping that this dosage will be more friendly to my hormone sensitive cells as hormonal cell cleansing is not a good idea.

Justfor_ profile image
Justfor_

March 2023 interim update:

Today, I was close the lab so walked in for a spontaneous PSA count. Long story short, stubbornly <0.01. Next step is dosage reduction to 25 mg/week and if this doesn't drive PSA above <0.01 then the BAT-like theory will become meaningful. Last time 25 mg/week tripled PSA in geometric increase, or shot-up 0.06 in linear terms (0.03 to 0.09).

PSA chart
Justfor_ profile image
Justfor_

April 2023 update:

This time I used the lab that reports to the 3rd decimal place. PSA at 0.015, came as a relief, as it dropped the undetectable "<" sign. The Bicalutamide concentration during this month has been ~80% of that of last November that derailed the control loop. Currently, I am undecided regarding the dosage to follow. I may maintain it as at present, that will probably increase next PSA count, or up it a bit that will probably stabilize or lower it. The thing I don't like with the latter is that there will be not enough visibility with the other two labs that report to the second decimal place. I will have to sleep on it.

PSA chart
Justfor_ profile image
Justfor_

May 2023 update:

I concluded last month's update with the line: "I will have to sleep on it". And indeed, it took me a couple of daytime-hours to decide upon the new dosage combined with a ton of algorithmic guesswork as to the projected PSA. When I say algorithmic guesswork, just imagine me pulling rabbits out of hats and squeezing them on the excel sheet with the historical data. Needless to say that the past three counts of <0.01 were not of any real help as they were not specific. Not to bother you any longer with my alchemy courses, I decided to increase the dosage by 50% (from 25 mg/week to 75 mg/2 weeks) anticipating a PSA of 0.018 to 0.022. Today's report came back at 0.020. Someone must be pulling my leg!!!

The good news is that my response to Bicalutamide is comparable to that of last year's. For this reason, this ongoing month I will be taking 50 mg (25 +25)/week like last year and monitor how it goes. The graph shows that both concentration and PSA went up this month, indicating a sub-critical dosage.

The usual graph
Justfor_ profile image
Justfor_

June 2023 update:

My algorithmic guesswork proved a total disaster. It predicted a slight rise, yet today's PSA test reported a slight decline from 0.020 (last) to 0.018 (now). More number crunching lies ahead. For this month dosage will be reduced to 44 mg/week, i.e. half a 50 mg tablet every 4 days. Google calendar app was set to remind me taking it.

The updated graph
PCJourneyman profile image
PCJourneyman

This is all good stuff and I respect your diligence and approach (as a semi-retired consultant engineer working in pharma/medical devices). I think for most, their Consultant/Physician would not be impressed (they like to work by the book and you are stealing their thunder) but it's your body! Primary thought from my side is what is the state of your PC? You are using Bical to 'manage' your PSA, but as all on this journey (should) know - PSA level does not have a direct or linear correlation to PC status/progression. Have you had scans along the way that align with your 'control'? Also you occasionally mention the beloved parallel Tamox along the way - were you proportioning dose of that in parallel?

Justfor_ profile image
Justfor_

Firstly, thank you for your kind words. To answer your question now, I have had MRI and CT scans post RP but not PSMA PET/CT. This month's update will be of special interest as I have contracted COVID a few days after my latest one. All options are open: a) No interference of COVID with PSA. b) PSA rise as PCa progresses with inflammation. c) PSA decline if cancerous cells were collateral damages of the immune system attack to COVID and it's tails. Also, doc prescribed two courses of antibiotics to protect me from secondary pneumonia. Some regiments comprise an antibiotic to fight PCa. We will soon know.

Justfor_ profile image
Justfor_

July 2023 special COVID update:

A few days past the June PSA test I contracted COVID. I became curious to find out whether it would interfere with my PSA control system. I can report now that, so far, it does NOT. My July PSA came out as expected at 0.020. During this past month I have lowered the dosage from 50 mg/week to 43,75. Bicalutamide serum concentration declined to 84% that of previous test and as anticipated there was a PSA rise from 0.018 to 0.020.

The updated graph
Justfor_ profile image
Justfor_

Update August 2023 - Scratching head time.

For this past month I maintained the half tablet per 4 days dosage like the previous month. Then PSA had risen from 0.018 to 0.020 and projecting this I anticipated 0.021-0.022. But the analyzer, Abbot i Alinity ΜΤ-24-01 with advertised min PSA detection limit of 0.003, wanted to play games with me and the report came back at 0.005! I can see 3 possible explanations for that:

1) Machine with ageing calibration. It is early August and most people are preparing for their summer vacations. "A leave it as it is now and we will take care of it when we return in late August or early September" attitude wouldn't surprise me.

2) As has been observed in animal adaptive dosage tests, but also in my own case after equilibrium had been established during a couple of months last year, only to follow a PSA decline at same dosage, this is a pattern that can repeat itself again.

3) The long shot: Cardiologist prescribed a Beta Blocker to deal with Tachycardia induced by long COVID that I have faced with very recently. Before taking the new medicine I run it by Google to see how it affects PCa. The result of this search was a mixed bag, some claiming that it has some beneficial contribution others that it is totally unrelated.

Now the difficult part: Should I reduce the Bicalutamide dosage to half a tablet every 5 days, or continue with the existing one and put off any adjustment for September?

The usual graph
Justfor_ profile image
Justfor_

Update September 2023

During August I decreased the Bicalutamide dosage down to 25mg every 5 days vs 25 mg every 4 days previously. On average, as there is latency involved due to the drug's long half life, the calculated Bicalutamide concentration dropped by 17% to 83% that of the August test. The PSA test came back at 0.011, thing that made me very happy. Going back to last month's post this rise in PSA points away from possible explanation 1) and more towards 2) or 3).

Hence, I did a search regarding Beta blockers and PCa and my findings are the following:

a) Early papers, up to 2015, find some benefit in Cancer Specific Survival (HR 0.78 and 0.85) without making any distinction between selective and non-selective Beta blockers. The one I am on is of the selective type.

b) Latest paper from Norway (2022) finds some benefit on BCR, but only for the non-selective variety.

c) There are another 2-3 papers that find no benefit whatsoever.

I will keep the current dosage during this month, as I would like to see how far up PSA can go due to inertia and seasonal change.

healthunlocked.com/fight-pr...

Justfor_ profile image
Justfor_

Update September 2023

graph
Justfor_ profile image
Justfor_

Update October 2023

Closing last month's update I was anticipating a PSA rise that finally didn't materialize. Instead, there was a slight decline, all within the precision of the test. PSA went, a hair, down from 0.011 to 0.010 (same lab and such). Maintaining the same Bicalutamide dosage until the next monthly test during early November. For testing purposes I will double the Beta blocker dosage from 1.25 to 2.5 mg/day.

October 5th 2023
MSTI profile image
MSTI

Hi Justfor, I have a question about DHT.

Build up of testosterone happens (as you had noted to 3755) when Bicalutamide is used.

Probably DHT rises too.

I have red in one member's post that his MO will not prescribe Bicalutamide without Finasteride or Dutasteride to have DHT under control.

What is your opinion ?

Justfor_ profile image
Justfor_ in reply to MSTI

It is reasonable indeed. DHT follows, on a percentage basis*, the amount of total Testosterone in blood. I do take Avodart daily (Dutasteride) and on top of that drink a freshly juiced grapefruit that increases the bioavailability of it. The trick with the grapefruit amplification originates from a video by Dr Snuffy Meyers. (*) To give you some indicative numbers, my DHT was counted to 2.31ng/ml at the extremity of the total T of 3755 ng/dl making it 6.15%. The mean of 15 DHT & tT pairs is 4.77%, SD 1.57% ranging it within one standard deviation (SD) of the mean.

MSTI profile image
MSTI in reply to Justfor_

Is Avodart dosage always the same or is changed according to Testosterone in blood or

maybe there is correlation with Bicalutamide dosage?

Justfor_ profile image
Justfor_ in reply to MSTI

For a very-very short period (~2 weeks) I tried two tablets per day instead of one. Didn't notice any major change in DHT %, so dropped the idea. But, Avodart has a very long half-life taking months to establish concentration steady state. So, I am not sure if there is a dose related effect.

MSTI profile image
MSTI

Thanks. Clear now.

Justfor_ profile image
Justfor_

Update November 2023 (Year 2 anniversary)

Seasonality and/or test variance out weighted any positive effect from the dosage doubling of the betablockers (everything else was kept unaltered). As of the 9th of November 2023 reported PSA is 0.016, a rise from the previous month's 0.010. Comparing that with last year's numbers, when there was a higher rise from 0.03 to 0.09 (different lab) but with the Bicalutamide dosage halved in between, the suspected seasonal variance seems becoming predominate. Current rise is welcome as my PSA target is 0.025-0.030. Thus, I will keep taking Bicalutamide at the current dosage (25 mg every 5 days) and if the PSA rise continues, so much the better. Driving into extinction all hormone sensitive cells is a BIG mistake. We need them to make life difficult to the resistant cells.

Justfor_ profile image
Justfor_

Two years of battling PCa.

9/11/2023
Justfor_ profile image
Justfor_

Update December 2023

Last month's PSA rise turned into this month's decline. From 0.016 it dropped to 0.012. I take the same dosage since the 1st of August (4.5 months now) and PSA swings in the range of 0.010 to 0.016 (average of 4 tests 0.012). For this coming month everything stays as before. Christmas period, time to relax and get lazy.

Daddysgirl83 profile image
Daddysgirl83 in reply to Justfor_

Impressive journey indeed! Some questions, what does the drs say about this? And is there a risk that the cells get resistant to biaclutamide at some point?Are you still thinking of going through Psma pet scan?

Justfor_ profile image
Justfor_ in reply to Daddysgirl83

1) I let the docs assume that I am taking the standard dose so a) they don't freak out and b) spare me their lecture. My life my decissions, not theirs.2) The theory of evolution claims that the more stress is applied to the hormone sensitive cells, the sooner the resistant clones will become dominant. That is what I am trying to avoid/postpone by limiting the dose to the minimum that maintains the equilibrium between those killed or put to sleep with the newborns. It is not the absolute value of the PSA that matters as most people believe and brag about undetectablity. It is the stability of the PSA that matters most IMO.

3) Of course, before salvage RT at a PSA over 0,2, after Bicalutamide has failed. When this will be, haven't the faintest idea. We will cross the bridge when we get there.

fast_eddie profile image
fast_eddie in reply to Justfor_

Was it your idea to go with the bicalutamide / dutasteride treatment plan? Are you dealing with a urologist or oncologist? Your efforts to actively manage your own treatment are laudable but like you say, likely to incur the wrath or disdain of your doctors. I am a retired engineer myself with a nodding acquaintance with control theory and such and I have a similar desire to tailor my own treatment and not just go along to get along. I've had a setback recently as I had to stop finesteride 5mg after it caused dental problems. I wonder if dutasteride would do the same.

Justfor_ profile image
Justfor_ in reply to fast_eddie

Now that you mentioned it, when I started taking Avodart after RP, I noticed some discomfort at my lower jaw. I consulted a dentist at a cancer-only hospital as my family dentist wouldn't know the answer to my query which was: "Is it possible that PCa bone metastases can hijack the jaw?" Her answer was: " It can be, but haven't run across any. Do you take (named a drug) that is known to effect jaw necrosis?" No, I responded, only Avodart. She didn't show any interest to continue any discussion related to the latter.

Justfor_ profile image
Justfor_

Update January 2024

Business as usual, i.e. PSA = 0.018, up from 0.012, 41 days ago. A very welcomed increase as relaxing the stress to the "good guys" (read the hormone sensitive cells) places roadblocks to the proliferation of the resistant clones. For this coming period, the 6th in a row, dosage will be kept at 25mg per 5 days.

MSTI profile image
MSTI

Hi Justfor,one silly question. If you had oportunity to do the same with enzalutamide, would you try it rather then bicalutamide?

Justfor_ profile image
Justfor_ in reply to MSTI

If the drug was sponsored -why not- I would be trully interested. Yet, starting from one (1) tablet per day instead of the MTD quad (4).

cfhny profile image
cfhny

Thank you Justfor. You and this type of information are exactly why I follow this forum.

Justfor_ profile image
Justfor_

Update March 2024

As we are leaving winter behind, I was anticipating a reasonable reduction in PSA, but not that much. January's 0.018, had a free-fall to 0.009 40 days later. It must be the variability of the test along with the seasonal effect to account for such a steep change. I can't explain it otherwise. Nonetheless, I am taking a very conservative reduction on the Bicalutamide dosage from the current (since early August 2023 to be exact) half 50mg tablet every 5 days to half a tablet every 6 days. The five day period was easy to remember, seven, i.e. same day each week, is even easier, but I will go very conservatively here and elect the "difficult" six day period. The equilibrium is working oscilating around positive and negative PSADT values and any change should be very feeble not to derail it.

Lastly, in the back of my head I keep this passage originating from Dr. Bob Gatenby.

"An unexpected observation from the animal study is that, over time, this approach requires lower and lower doses to maintain control resulting eventually in stable tumors that required no therapy (the mice eventually die of old age)."

Who knows, maybe in the end I will append my nick name to Justformice.

Justfor_ profile image
Justfor_

And the usual graph:

March 4th 2024

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