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Post CK Update -- Measures of Reoccurence?

Swingshiftworker
Posts: 626
Joined: Mar 2010

Took a PSA test on 9/12 -- it was 3.56.

Just slightly lower than in June (3.72), slightly higher than in March (3.03) and only slightly lower than in Jan 2010 (4.5) before my biopsy that led to CK treatment in Sept 2010.

Don't know what this means. It has been essentially "flat" for the past 9 months, after going up as high as 29.7 (post biopsy) and 12.30 (post treatment). The trend is generally down but it's no where near where other people (like Kongo) say their post-RT PSA test levels (below 1) were a few months after treatment and is certainly no where near post RP levels below (0.1).

The radiation oncologist says that I might have to wait up to 4 years to hit a nadir and everything is fine if it doesn't go up, but I'm not willing to wait THAT long, especially if the results are not trending down as quickly they "should" be.

Does anyone happen know the degree of error in PSA test results AND does anyone know what the typical post-RT PSA levels (for any kind of radiation treatment -- IMRT, CK, BT, PBT or whatever) are for men 1 year post treatment?

I've seen discussions (but no data) suggesting that the margin of error in PSA testing can be as much as +/- 10% and I've also found an article that suggests that 1.5 is a marker for success post-RT, that PSA levels should drop w/in 18-24 months and that constant (level) or rising results indicates reoccurrence.

See: http://www.betterhealthresearch.com/news/psa-levels-two-years-after-radiation-treatment-may-indicate-cancer-recurrence-chances-19543926/

I think I'm going to use this article as a baseline for further action and, if my PSA results don't reach 1.5 w/in the next 6-12 months, I'm going to red flag it for further testing/treatment.

Sent an email to my radiation oncologist asking for his opinion on this. Will let you all know what he says in reply.

VascodaGama's picture
VascodaGama
Posts: 1535
Joined: Nov 2010

Swing

Back in 2000 the threshold value indicating success for RT was nPSA=1.
In one study done by ASCO in 1999, several data were raised which provided the basis for present standards of ASTRO. They confirm recurrence based on positive biopsies taken periodically. “None Evidence of Disease” was declared in cases with negative biopsy and PSA less than 2. Biochemical failure corresponded to a PSA greater than 2 and rising.
Overall the study indicates that the median time to get to nadir was between 22 to 27 months, and that nPSA levels were between 0.3 to 0.5.
This study is very comprehensive and it also proved higher success rates for increased doses of radiation and to the benefits of HT in the RT treatment. Patients have been treated with the old EBR equipment but such shouldn’t be considered erroneous when comparing with the results of RT done with modern recent modalities.

You can read the context in this site;
http://www.astro.org/PublicPolicy/WhitePapersAndOtherDocuments/documents/prosrtguid.pdf

In an article from Johns Hopkins, they predict failure or success of biochemical recurrence based on two standards; ASTRO and AUA. They consider that any PSA above 0.2 is indicative of recurrence based on the 1 to 1.5 theory (your numbers) which are supposed to correspond to the PSA produced by approximately 10 to 15 grams of prostate (the portion still alive of radiated prostate).
In CK cases with high doses of exposure and precision on the application, the prostate is seen as 100% “dead”, therefore such theory if applied should correspond to a must lower level threshold PSA.

You can read the context in this site;
http://urology.jhu.edu/newsletter/prostate_cancer64.php

In my opinion ASTRO way for predicting recurrence is conservative but reliable;
“PSA test every three or four months during the first two years after treatment, and every six months after that.”
“Failure is the midpoint between the PSA nadir and the first of the three consecutive rises.”

You could always subject to a biopsy to get a final answer, if your radiologist sees it proper to be done after CK.

Wishing you a continuous decrease in the results.
VGama

Kongo's picture
Kongo
Posts: 1167
Joined: Mar 2010

Swing, I certainly appreciate your frustration. Hopefully, your radiation oncologist will have some technical details that will make you feel comfortable.

The one thing that I think you should keep in your mind is that your PSA is not going up which is a sign that prostate cancer may be continuing. Since those of us who have had CK still have a prostate there will always be some PSA and my radiologist has also told me that it often takes three to four years for a solid nadir to be established. All of the things that can cause PSA to spike are still valid for men who have had CK as a mono therapy such as sex before a blood draw, a digital exam before the blood draw, a hard stool, and even some over the counter medication (like Advil) can all cause PSA to go up.

Most men have seen a more dramatic drop than you have experienced. In my own case, I was told that my drop was faster than normal. At 0.8 at one year the rate of drop for me seems to be slowing but apparently has not settled out. Nadir for each case is going to be different although most are less than 1 at the two year point--at least according to my doctor.

I also recall that you have had some pesky prostatitus following your CK which could also delay the drop in your overall PSA levels and is probably, at least in my opinion, the culprit here, particularly if it is still ongoing. It will be interesting to read what your radiation oncologist says.

You've read all the studies and I know you know that there are virtually no failures for men with your initial pathology after receiving CK treatment at this early stage. I doubt very much that you will be the first.

In the meantime, I share your concerns and will be thinking good thoughts for you.

Best,

K

Swingshiftworker
Posts: 626
Joined: Mar 2010

My radiation oncologist (RO) said not to worry -- "Everything's on course."

I have trouble accepting this "diagnosis," given the lack of any significant change in my PSA over the past 9 months. I told my RO that I'd wait another year but, if my PSA doesn't drop to below 1.5 w/in 2 years, I'll ask for a reassessment.

What I didn't say to him was that, if there's no significant movement towards a PSA of 1.5 by next Sept 2012, I'll go elsewhere to get an additional biopsy and/or scans to see if the cancer is still there or not, if he's not willing to approve them.

The flat PSA level in the 3-4 range may just be due to a continuing prostatitis but I'm skeptical. I've made a point of not having sex or even going to the bathroom before my PSA tests so as not to spike them, but the results are still elevated and inconsistent.

Most but not all CK treatments have been successful but there's no reason yet to believe why I might NOT be among the failures given my current stats. I'm not going to dwell on it but I believe in actively managing my cancer and will take further action if my PSA levels d not drop to below 1.5 w/in the next year.

We'll see . . .

BTW, following below is the link to the Memorial Sloan-Kettering Cancer Center study (published in Dec 2009) which concludes that any man w/a PSA still above 1.5 two years after RT should be evaluated for "presence of nonresponding disease" (ie., continuing prostate cancer) and "earlier salvage treatment interventions should be considered."

http://www.redjournal.org/article/S0360-3016%2809%2900045-5/abstract

hopeful and opt...
Posts: 1293
Joined: Apr 2009

In Jan 2010 your PSA was at 4.5 before your Sept 2010 procedure. Your PSA has dropped significantly to 3.56. During the last 9 months it has held at this level.

To me there has been a decline, and can continue to nadar in the next year.

My question is, What is the rate of change at the one year time period, after succesful treatment that is reported by others who have received CK . Is this information available?

VascodaGama's picture
VascodaGama
Posts: 1535
Joined: Nov 2010

Swing

Waiting may be your best shot to deal with your “plateaued” PSA. A late decrease in PSA after radiotherapy seems to have better prognosis in terms of biochemical recurrence.
In the Journal of the European Society for Therapeutic Radiotherapy & Oncology they report on a study done to verify the relationship between biochemical failure and time to nadir in patients treated with external beam therapy for T1-T3 prostate carcinoma, as follows;
“PSA nadir, after radical radiation therapy for prostate cancer, is an important predictor of BDFS (Biochemical disease-free survival). PSA nadir ≤1 ng/ml is associated with a favourable biochemical outcome. Patients, who reach PSA nadir more than 1 year after completion of radiation, have a better prognosis than patients with early response. PSA nadir can be a useful tool in judging the efficacy of treatment, and to compare the different treatment regimens much earlier than relying on clinical relapse. In addition to PSA nadir, time to nadir, pretreatment PSA and Gleason score are independent predictors of BDFS on multivariate analysis.”

Here are details on the study;
http://www.thegreenjournal.com/article/PIIS0167814098000619/fulltext#article-outline

In regards to CK, the CENTRO DIAGNOSTICO ITALIANO (CyberKnife Center) in Milan, Italy, have reported on their preliminary experience with Cyberknife in 73 patients with clinically localized prostate cancer (T1c and T2b), which have been treated between July 2007 and September 2010, and with a follow up every 3 months for 3 years. In the report they comment that the patterns of PSA response show a gradual decline with a PSA nadir below 1.0 ng.ml after 12 months. However there is no indication on failure due to a higher Nadir at the 12-months mark. In the report they say that;
“Three patients experienced incontinence, (two 12 months after the treatment, one 27 months later). One patient experienced rectal incontinence 12 months after the treatment.” Only two patients have failed biochemically, but they were high risk Gs8 patients.

Hope this information is of help in your quest.

VGama

Swingshiftworker
Posts: 626
Joined: Mar 2010

Thanks for the info, Vasco.

This is somewhat reassuring but it looks like PSA 1 is still an important target 2 years out in order to insure the likelihood of "success." I can only hope that my PSA will break out of its current plateau and decline to that level in the next 12 months.

VascodaGama's picture
VascodaGama
Posts: 1535
Joined: Nov 2010

Swing

Do not fall in the trap of anxiety. Stress is the best friend of the bandit.
You may be right with regards of a nadir equal to or less than 1, but based on info at hand, nothing suggests that you will not get to that level.
Cases used in the European study considered “negative to recurrence”, were of guys that reached the PSA nadir of <1 ng/ml, in a spanned period ranging from 2 to 43 months. We know that you were not one belonging to the beginners in the scale but you could be one in the latter periods of the scale, which reaches over the 3.5 years mark.

Enjoy your symptomless successful treatment and let time take its course. If something is to come that will be and you would deal well at the time.
Enjoy life, do some travel, play your Sudoku and leave stress at the doorsteps.

Regards
VGama

Swingshiftworker
Posts: 626
Joined: Mar 2010

Vasco:

I'm not unduly stressed or anxious about the PSA pattern "yet" -- just concerned (as I think I should be)-- and I'm certainly not dwelling on the "problem."

In fact, I have thought about it in depth only when the quarterly PSA test results have come in. We'll just have to see where it is in a year and then reassess the situation at that time.

If it rises 3 times w/in that time period, the answer is clear. The CK has failed. What is unclear is if it decreases but not to below 1 w/in that time period.

We'll see . . .

silverfox1
Posts: 36
Joined: Dec 2010

Swing,
I cannot add to the resources that the others provided you with. But what I can do is keep you in my thoughts and prayers. You have provided a lot of support not only to myself, but to others as well. I am glad that you are sharing your concerns with us. I wished I could do more to help! Keep the faith!

Walter

silverfox1
Posts: 36
Joined: Dec 2010

Swing,

I have been visiting and using as a resource the "Cyberknife Patient Forum" web site. You might want to visit the site and compare your PSA notes with others. This site is devoted to CK treatment patients. There is also an RO that moniters the site and will respond to any of your questions. He provides his email adress if you prefer to keep your questions confidential. Give it a try, there were a few guys that shared your PSA history and had posted their concerns as well.

Walter

Swingshiftworker
Posts: 626
Joined: Mar 2010

I haven't been over there for awhile and just logged in to take a look.

Saw a couple of recent threads regarding post-CK treatment PSA concerns but didn't note any mention of my specific situation. If you have a link to a particular thread of interest, please forward it to me here.

Thanks!

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