Erratic PSA and broken bone

[MechD]

My condition is mCRPC. Treatment from Jan. 2022 through Feb 2023 was Cabazitaxil + Carboplatin + Prednisone + Lupron. My PSA has slowly crept up from July of last year to Feb of this year with the numbers as follows:

07/06/2022: 0.40

02/13/2023: 2.33

03/07/2023: 0.03

04/14/2023: 6.92

Only changes were: started vegetarian diet last fall, discontinued chemo in Feb 2023, started Xtandi 04/04/2023, broke bone in foot (metatarsal) 04/05/2023.

I'm resuming chemo this Friday due to PSA spike and staying on Xtandi.

Any thoughts as to why my PSA was so erratic lately with the sudden drop to 0.023 and then spike to 6.9? Could it be stress related to the broken bone?

Thanks.

[Derf4223]

pubmed.ncbi.nlm.nih.gov/183...

Abstract

Background: Chemotherapy has emerged as a standard treatment in patients with castration-refractory prostate cancer (CRPC). Consensus criteria are available to define response in CRPC as at least a 50% decline in serum prostate-specific antigen (PSA) confirmed 4 weeks later. The objective of this work was to study early serum PSA changes in patients under chemotherapy and to correlate these changes with subsequent response assessment.

Patients and methods: Serum PSA levels were monitored every 3 weeks in 79 patients with CRPC treated with chemotherapy and a time course of serum PSA levels was obtained. Correlation with response was studied.

Results: According to consensus criteria, 21 (40%) and 20 (38%) patients achieved a PSA response and stabilization, respectively, after first-line chemotherapy. Among patients who achieved either a response or a stabilization, 8 of 41 (20%) had a serum PSA rise during the first 8 weeks of chemotherapy, followed by a subsequent decline in serum PSA. The same observation was made in patients receiving second-line chemotherapy: 6 of 20 patients achieving a response or stabilization had an initial serum PSA rise. The postchemotherapy increase in serum PSA could reach more than twice the baseline value. The duration of the PSA surge ranged from 1 to 8 weeks. When considering responders only, 6 of 30 (20%) had a postchemotherapy serum PSA surge, followed by a drop.

Conclusion: Postchemotherapy PSA surges occur not infrequently in patients with CRPC who respond to chemotherapy. Physicians should be aware of this effect to avoid inadequate early discontinuation of chemotherapy.

[MechD in reply to Derf4223]

Thank you for sharing the info.

[pdaleuski]

MechD

I have been on Extandi for over two years; my PSA went from 358 to .1, then back up to .2, and has stayed there for six months. The only drawback I have had is fatigue and some hot flashes, and am easy to bruise. All in all, it saved my life lets see how long it lasts. Hope this helps you and stay in there. NO radiation or Chemo...as if date.

[MechD in reply to pdaleuski]

That’s good news, what a great response you’ve had! I have those side affects as well but manageable.