Prostox - learn about whether radiation will cause problems

@kjholz
In this case, they recommend low-dose brachytherapy. Did they mention that in your documentation?

@jeffmarc I re-watched the video. Dr. Weidhaas says:

"...but low-dose Brachytherapy is really not like anything we've talked about. It's such a low delivery, slow, slow delivery of radiation. Weer actually doing a study right now to see if our Prostox Standard predicts that or if it's a signature on its own."

So, no, she did not recommend low-dose Brachytherapy.

And in our Prostox report, there's no mention of any alternative treatment. Here's all we got:

"INTERPRETATION
Based on the genetic biomarkers assayed, the patient falls in the categories of:

• HIGH RISK for SBRT
• HIGH RISK for CFRT

For Developing Grade ≥ 2 late genitourinary TOXICITY after prostate directed treatment.

NOTES

For PROSTOX ultra: DNA was isolated from the swab specimen submitted and amplified using quantitative real-time polymerase chain reaction (RT-PCR) to genotype 32 microRNA-related germline variants. Based on the results of the analysis a proprietary algorithm was used to calculate the risk of significant (grade ≥ 2) late genitourinary toxicity following stereotactic body radiosurgery (SBRT).

The PROSTOX ultra signature has a negative predictive value (NPV) of 96%, a positive predictive value (PPV) of 89%, specificity of 95% and sensitivity of 79%. A high-risk result predicts a patient toxicity risk of ~65-80%, and a low-risk result predicts a patient toxicity risk of ~4-7%. A patient with a high-risk result is ~8-10 times more likely to experience toxicity following SBRT than a patient with a low-risk result.

For PROSTOX CFRT: DNA was isolated from the swab specimen submitted and amplified using an Agena MassARRAY to analyze 21 microRNA-related germline variants. Based on the results of the analysis a proprietary algorithm was used to calculate the risk of significant (grade ≥ 2) late genitourinary toxicity following conventionally fractionated radiation therapy (CFRT).

The PROSTOX CFRT signature has a negative predictive value (NPV) of 95%, a positive predictive value (PPV) of 72%, specificity of 94% and sensitivity of 76%. A high-risk result predicts a patient toxicity risk of ~60%, and a low-risk result predicts a patient toxicity risk of ~4.6%. A patient with a high-risk result is ~12 times more likely to experience toxicity following CFRT than a patient with a low-risk result. Comparatively, receiving a high risk result here means someone is about 4 times as likely to experience toxicity than the general public without a genetic test.

These tests have not been approved by the United States Food and Drug Administration and should not be used as the sole indicator of risk in determining treatment.

Limitations: Results do not predict a patient’s likelihood of clinical response, short-term side effects, or non-urinary side effects from SBRT or CFRT. A low-risk result does not rule out any possibility that the patient will experience toxicity, and a high-risk result does not guarantee that the patient will develop toxicity. Results should only be used as part of the
consideration of treatment choice."

That's it. Imagine how we felt when both our urologist and radiation oncologist talked about "cured" and then you see "• HIGH RISK for SBRT • HIGH RISK for CFRT" on your computer screen.

Cheers.

@kjholz
Did you watch the video from the latest meeting that we had this week? In there, she says that low-dose brachytherapy is probably safe for those that failed both tests.

You can always pick to have surgery, but that doesn’t always work either. If the cancer has spread outside the prostate surgery is not sufficient. Some type of radiation will be necessary.

@jeffmarc Yes, I watched the entire video. And she does not say that lose-dose brachytherapy is probably safe for those how failed both Prostox tests.

Here is a transcript of what Dr. Weidhaas ssaid:

"...but low-dose Brachytherapy is really not like anything we've talked about. It's such a low delivery, slow, slow delivery of radiation. We're actually doing a study right now to see if our Prostox Standard predicts that or if it's a signature on its own."

That's Weidhaas speculating low-dose might be ok. But not knowing. Based on her above comment, I sure wouldn't get seeds planted in me when I'm a Prostox Double High Risk.

Based on our Prostox scores, our imaging/biopsies etc Grade 2, 3+4, we opted (and got accepted) for Tulsa Pro. We have low-bar hopes --QOL for three years and then (because I'm a pessimist) the inevitable rise...

@kjholz
I guess when she discussed about how it was not like the other radiation treatment, since it had such a low delivery and slow delivery of radiation it sort of implied it was safer than other methods. I can understand you’re using TulsaPro. LDR brachytherapy Has limited uses and is not useful for a really severe case of prostate cancer where the whole prostate is involved. In that case TulsaPro Definitely seems to meet your requirements.

I guess those in the 1% or 2% will wait for Studies to complete on that procedure as well.

This does leave a big hole in treatment for people that have a lot of cancer in their prostate as well as seminal vesicle invasion or EPE or ECE or even cribriform and intraductal. If they are among that 1% or 2% that can have problems with both EBRT and SBRT it may just leave Them to have to face those are the only options available today, And there will be long-term side effects from the radiation. A very difficult situation.

Hi again. You wrote:

"[Low-dose Brachytherapy] Has limited uses and is not useful for a really severe case of prostate cancer where the whole prostate is involved. In that case TulsaPro Definitely seems to meet your requirements."

Tulsa Pro is also not good for severe/really severe cases either. Its "sweet spot" is Grade 2 Intermediate (3+4 with the less percent 4, the better). You can be accepted for Tulsa Pro if you're 4+3. Has to be confined to the prostate. The "sweet spot" is 3+4 though.

And you're right. For people that have a lot of cancer in their prostate as well as seminal vesicle invasion or EPE or ECE or even cribriform and intraductal *with* Prostox "High Risk" for both SBRT and IMRT piled atop all that....

...(thinking) looks like only ADT or take a chance on radiation with odds very much not in your favour.

"Limitations: Results do not predict a patient’s likelihood of clinical response, short-term side effects, or non-urinary side effects from SBRT or CFRT. "

Um so Prostox is only reporting on Urinary problems post radiation - not anything else, like lower GI tract issues?

@jeffmarc
Thanks Jeff, really good to know!

@klein505 That is correct no claims are made for predicting GI effects. Logically there should be a lot of correlation between the GU and GI risk since the test covers genetic risk from DNA repair, response to stress and inflammation. GI risk is probably not as predictable since it is also related to radiation being off target and the use of spacer gel.

Thanks for helping us learn about Prostox.

I was able to participate in the April 27th webinar.

Met with Radiation Oncologist on April 30th to discuss possible SBRT or HDR treatments.

Radiation Oncologist had not heard of the Prostox test. I gave her information about the test and asked for the test.

MiraDx just emailed indicated Prostox test kit is on the way.

All this is due to each of you sharing info.

Thanks.