I finished 33 sessions of IMRT on 3 lymph nodes (the only 3 places where the new PET scan specific for prostate cancer revealed cancer) 6 weeks ago but my PSA is still rising. Radiation oncologist said he was disappointed that my PSA didn't stay the same or go down after that amount of time but that, hopefully, in time it will begin to go down. My prostate was removed 3 years ago so that was not an issue. I do have 5-6 bone metastases but they are inactive at present (no pain and they currently don't show up on bone scans, CT scans, or the new PET scan specific for prostate cancer). Anyone have any comments and/or experience with PSA decrease time after IMRT on only known active metastases? Thanks.
6 weeks after radiation my PSA is sti... - Advanced Prostate...
My IMRT did produce a drop in PSA at six weeks, but the nadir came at twelve weeks and held for a few years. Are you still taking ADT? Good work on clearing up your bone mets! Xofigo is a great treatment if the bone mets ever return.
Thank you, Bob. Yes, I am still on ADT -- Lupron injections and Xtandi. In addition, I receive a Xgeva injection every 28 days for the bones. At this point, my oncologist says that my bone mets are inactive -- he says that he does not know whether they are still there but inactive or gone so, for now, has to assume that they are inactive to be on the safe side.
Which pet scan?
Good Morning Ed,
I recently had proton beam radiation: 44 treatments to prostate and 25 + 5 boost to lymph nodes. This was 4+ years since diagnosis with metastatic lymph node disease and after all drugs.
PSA at start was 2.62 and nadir at end was .46. Then PSA began to rise again, reaching 4.59 3 months later, so now onto chemo.
It may take several months for the full effect of your radiation to be reflected in your PSA. My Med Onc likened radiation to "spot welding", it hits its target but anything else is missed.
You have many other options in this war, so stay strong.
Best wishes. Never Give In.
I have not had the experience of Radiation, as I failed the ability to have it after surgery, because my PSA was too high after surgery, and the best guess by Docs. was that I was already metastatic, at the time of surgery. WE attacked with a specially designed Drug/Supplemental program. And So far OK.
But in your case, we have lots of responders here and on another site that report the same situation, with no drop to PSA, or slightly rising PSA over a period of 2 months---and then it dropped. Why I do not know---but my guess is the Pca cells get wacked and some may die quickly, and others are punch drunk, still giving off the antigen, but not able to do further damage. Some may have survived without damage. The punch drunk cells may remain as unwanted live material, but have lost their complete function, which is to kill you.
In my studies--I came across certain type pathologies, that are more resistant to radiation than others. Supposedly Ductal and Small Cell PCA's are more resistant, than your every day type pathology. Do you know your pathology very well???
Going on to Chemo, you may experience a similar situation, of a temporary rise, but after a certain time, or number of treatments, you should get the drop in PSA you are looking for.
Nalakrats, thank you very much for your very informative and, encouraging reply. I have to say that I do not know my pathology well -- I do not know what Ductal, small cell PCA's, or every day type pathology even is. I will ask my oncologist about this. Thank you again.
My understanding of radiation is similar to yours. They don't give you enough radiation to outright kill the tumor cells. If they did, it would do too much damage to the surrounding tissue. However they do give enough to ionize (i.e., knock electrons off atoms in the cell) many molecules, including DNA molecules. Ionization causes the DNA molecules to acquire a positive charge, which makes them react with negatively charged molecules in the nucleus, which effectively disables the DNA. Tumor cells typically already have damaged DNA repair facilities, and they can't repair the damage and eventually die from it. In the meantime, they may actually give off more PSA than normal for the same reason that prostatitis or other irritations and inflammations of the prostate produce more PSA.
I think what this means is that, while your PSA news isn't good, it might not be quite as bad as it appears. It's possible that your PSA will "bounce" up and down for a while but not necessarily start a big upward climb.
Best of luck.
Thanks for a possible chemistry explanation to a Chemist. The PSA--can be mystifying, at times.
Great news! -- I just had a blood sample taken this last week -- 10 weeks after finishing the IMRT treatments. My PSA decreased 35 percent from where it was 6 weeks after IMRT!! I really appreciate all the great advice and comments from everyone earlier.
That's very good news EdMiller.
I share that rising PSA dilemma with prostate bed external radiation. Using Estogen patches PSA had decreased from 12 to 1.4 over three months. In first three weeks of radiation therapy PSA suddenly increased to 1.9. I have to ask my radiation oncologist and clinical oncologist about this but explanations and experience by all above gives me some comfort.
Ed, I'm glad it's going in the right direction. My doctors told me before my IGRT began that they will not do a psa test again until 3 months after the radiation therapy ends. Your 10 week psa test is right in that neighborhood.