PSA level post HT & RT

nprfrommumbai

Hi All,

My father, at the age of 66, was diagnosed with prostate cancer in the first week of June 2011 with a psa of 29. After a biopsy, the cancer was graded a 6 (3+3) on the Gleason scale, however the report did not mention how many samples tested positive for cancer. An ultrasound report mentioned the tumor being about 60 gms (what is the significance of this?) and no apparent seminal vesicle involvement (I guess this is good). Bone, CT, MRI and PET scans were all clean and no signs of metastasis was detected. (Bone scan had detected a minor hot spot at the top of the spine, however further investigation through MRI and PET scans came back negative, big relief!).

After a lot of discussion, we went in for surgical castration on the 9th of June and started 40 sessions of radiotherapy (IMRT) in the middle of August, 9 sessions remaining. His psa 2-3 weeks after castration was 1. Thankfully his radio therapy sessions have been uneventful with no major irritation while passing stool or urine.

Now, the radiation oncologist told my father yesterday that future course of action will be a six monthly psa test, however ( to a question posed by my father) he went on to state that the psa might never be zero and we should expect it to be a low single digit number, which is absolutely fine. This has completely confused me, based on what I have read here and on yananow, a first indicator of cancer in remission is a psa at or heading towards zero. Btw he is on casodex currently, and the radio onc also told him he can go off casodex in a short time.

Is there a different psa measure which can be above zero for people who have been through HT & RT? Any thoughts/ comments would be much appreciated!

Also, the posts on this forum have been of immense help to us in understanding how to tackle this disease and what to expect going forward. I think together with yananow this forum is the best resource for people dealing with PCa.

Thank You
npr

VascodaGama

Zero on your Father's Case could be equal to a Digit Number
NPR

I would recommend you to get a copy of the pathologist’s report on the biopsy. This is the only element that can assure to your father a correct diagnosis. The ultrasound indicating a “tumour of 60 gms” may be in reference to the prostate gland, but the usual normal size of a prostate is between 25 to 45 gms. If the reference is the prostate size, it could mean that your father may have/had benign prostate hyperplasia (BPH) which is an inflammation not cancerous of the prostate.

The significance of this fact is small but it could be one of the causes justifying a portion of the high PSA at 29, before treatment. This high level qualifies your father’s case in a high risk for recurrence, even if his Gleason score is the lowest in aggressivity.
This may be the reason for your father’s doctor choice in a combination of hormonal treatment plus radiotherapy. Castration (surgical or chemical) is an excellent modality for dealing with any systemic cancer by lowering the level of testosterone (food of the cancer), and the radiation will “kill” the cancer standing at its target.

The success is verified through a periodical PSA test. In radiation treatments solo (in cases with the prostate gland in place) this test is recommended to be taken three month post treatment because the radiation will cause inflammation of the prostate tissue which will produce a higher “masked” PSA. Radiation does not cause a “sudden” death of all cancerous cells too. These will take time to die because of the damage caused to its DNA, making it difficult to multiply. In some cases it takes over two years.

In combination cases similar to your father’s (HT+RT), the PSA as a marker is somehow obscured because of the two possible factors behind the production of the serum. The portion of benign prostate (assumed by some doctors as being 1 to 1.5 ng/ml, which represents about 10% of the volume of living prostate after RT); and the portion, if any, related to cancer which production has been impaired by the hormonal treatment.

One could say that for some doctors a PSA post RT treatment in the digital levels of 1 is indicative of a successful treatment whether for others a much lower PSA of 0.2 to 0.5 is the threshold of success.
Nevertheless, all successful cases can only be declared if the PSA reaches to a plateau and stays there forever. Any substantial increase of PSA on a continuous pattern after it reached its nadir and stoped, is significative of cancer activity and therefore declared recurrence.

Your father’s doctor opinion on the post treatment PSA is correct if any portion of living prostate is left untouched. The quantity of produced serum PSA is related to the benign glands volume.

Welcome to the board. I wish your father a good recovery from the treatment.

VGama