My Oncologist enrolled me in ct DNA study he is conducting.

[Splash1953]

Back in November 2024 my Oncologist enrolled me in a cy DNA study he is conducting. I am currently undergoing treatment with Chemo and Eligard. I have completed 22 cycles of Chemo with more scheduled every three weeks. My routine is I get bloodwork the day I see him and get approved for Chemo the following week. Now when I get the bloodwork they send in a ct DNA kit which contains two vials. So three vials now of which two go back in box and go to DNA lab. So far I have had three of these tests. I saw my oncologist on Monday and he said the first DNA test results came back and showed no cancer in my blood. He said this is remarkable but wants to see more results. What’is odd is since I started Chemo back in August 2023 my PSA was 8. It has bounced up and down during this period where my low was three and my high went up 7. I also had scans in August 2023 and then a new one in September 2024 that showed no changes or new Mets to bones ( I have no Mets to nodes or organs just 18 Mets to various bones). It is my understanding that this DNA test can even detect micro cancer cells floating around the bloodstream. Hopefully the future results will continue to show no cancer activity in blood and we can stop the Chemo. Unfortunately I really couldn’t ask any questions on Monday because I had a very bad case of laryngitis and could not talk at all. lol

[GP24]

Circulating tumor DNA (ctDNA) is the DNA of tumor cells that have died, not the cells. I have heard that usually you have enough ctDNA so that it can be detected when the PSA value is above ten. medlineplus.gov/genetics/un...

[Splash1953 in reply to GP24]

Thanks for the reply.

[Mgtd in reply to GP24]

Thanks that was really interesting. See my comment below.

[Mgtd]

Thanks was interesting. At my last MO meeting, she told me she was going to do a ctDNA test at my next blood draw. I get that blood work on this coming Monday. My next visit after that is in 2 weeks. How long before you get got the results back?

Last time we met she told me she was interested to track my potential remission progress. I think she is using me to build her knowledge base since I maybe an ideal candidate for her to track for a lot of reasons.

Should be an interesting experience to see how this all works in my case.

[j-o-h-n in reply to Mgtd]

"ideal candidate for her to track for a lot of reasons".

Careful she may be on the lookout for other, shall we say, reasons? LOL

Good Luck, Good Health and Good Humor.

j-o-h-n

[Mgtd in reply to j-o-h-n]

LOL!

[GP24]

Mgtd, I think your PSA value is too low to detect any ctDNA. The studies were done with patients which were castrate resistant.

This is a video of a ctDNA trial in Melbourne to measure the response of the patients to a Lutetium therapy. (The presenter gives me the impression she did not want to present this at all) youtube.com/watch?v=cn1_6jn...(Not working as expected?) The patients in this trial had a median PSA of 71.5 ng/ml.

This are some recent articles about determining ctDNA fraction in CRPC prostate cancer patients:

pmc.ncbi.nlm.nih.gov/articl...

aacrjournals.org/clincancer... (the median PSA was 45 ng/ml])

ascopubs.org/doi/10.1200/JC...

[Mgtd in reply to GP24]

Then I guess I will find out more fully why she is doing this next week. I will update you then. Stay tuned. She must have some thoughts that I am not aware of.

[dhccpa]

Is that a very low dose of chemo? 22 sounds like a horror movie!

[Splash1953 in reply to dhccpa]

I do a full dose of Chemo every three weeks. Believe it or not it hasn’t been to bad with side effects. Days 2&3 use to be stay in bed or chair days. Now I am up and about. Have a little Neuphothy in feet and hands and loss of taste except chocolate Ice Cream. My Onco had a guy on Chemo for 3 1/2 years. I also read a story the other day a woman with Pancreatic Cancer has had over 180 cycles of Chemo and she runs marathons . My oncologist keeps a strong eye on my bloodwork every three weeks.

[dhccpa in reply to Splash1953]

That's great that you're holding up. Never heard of anywhere near that many. Carry on!

[j-o-h-n]

Laryngitis treatment, Splash with plenty of fluids (also salt water).

Good Luck, Good Health and Good Humor.

j-o-h-n

[Splash1953 in reply to j-o-h-n]

Thanks John , will do with the salt water. I drank more tea these past two weeks then what was on the ships of the Boston Tea Party. But Ice Cream seems to work also. Lol

[j-o-h-n]

11th Commandment: Ice cream always works.........

Good Luck, Good Health and Good Humor.

j-o-h-n