HealingWell
Search Close Search
☰

Prostate Cancer Risk Calculator

Support Forums
>
Prostate Cancer
✚ New Topic ✚ Reply
12
❬ ❬ Previous Thread |Next Thread ❭ ❭
Posted 7/31/2013 5:51 PM (GMT 0)
In another thread -  "Report suggests changes in the definition of what is cancer" - I added a post that talked about one of the additional proposals by the panel of experts that had to do with "mitigating overdiagnosis."  That portion of the panel's recommendation included the use of a calculator that would help predict what sort of tumor is likely to be found if a prostate biopsy was done based on PSA and DRE results:

"We can, for example, do a fairly good job before a biopsy of the prostate is performed of predicting what sort of tumor is most likely to be found (a slow-growing likely inconsequential tumor or a fast-growing lethal tumor) with a risk calculator such as the Prostate Cancer Prevention Trial Prostate Cancer Risk Calculator (PCPTRC)."

Please also note, to keep this in context - "The PCPTRC is applicable for men who are undergoing prostate cancer screening with PSA and DRE as it was derived from a group of men in the Prostate Cancer Prevention Trial who underwent annual PSA and DRE screening. The risk estimate from the calculator does not reflect an endorsement of either PSA or DRE for screening for prostate cancer."  (Bold and underline added by me)

Here are the restrictions for using this Calculator:

"The calculator is in principle only applicable to men under the following restrictions:

  • Age 55 or older
  • No previous diagnosis of prostate cancer (NOTE: You have to put "Never Had a Biopsy" in the final field)
  • DRE and PSA results less than 1 year old"

I thought it would be interesting to start a thread on this, and others have concurred, so here it is.

I ran my numbers and will provide that as the first post/exercise/results.

Posted 7/31/2013 5:52 PM (GMT 0)
A Yooper:
Results

Based on the data provided, the person's estimated risk of biopsy-detectable prostate cancer is 42.4%.

The 95% Confidence Interval for this prediction is 39.1% to 45.8%.
More information about the confidence interval

The person's estimated risk of biopsy-detectable high grade prostate cancer is 9.5%.

The 95% Confidence Interval for this prediction is 6.1% to 12.8%.
More information about the confidence interval

Posted 7/31/2013 6:01 PM (GMT 0)
Here's mine...

Based on the data provided, the person's estimated risk of biopsy-detectable prostate cancer is 36%.

The 95% Confidence Interval for this prediction is 30.6% to 41.3%.
More information about the confidence interval

The person's estimated risk of biopsy-detectable high grade prostate cancer is 5.8%.

The 95% Confidence Interval for this prediction is 3.1% to 8.5%.
More information about the confidence interval
Posted 7/31/2013 6:31 PM (GMT 0)
Once again I don't fit anything:

Based on the data provided, the person's estimated risk of biopsy-detectable prostate cancer is 68.7%.

The 95% Confidence Interval for this prediction is 63.6% to 73.7%.
The person's estimated risk of biopsy-detectable high grade prostate cancer is 27.3%.The 95% Confidence Interval for this prediction is 17.7% to 36.9%.

I came out of biopsy with 9 cores positive for 4+3 & 4+4, post op 4+5, 40% involved.

27%. Sure. Would have helped me make a good decision? No.

Posted 7/31/2013 7:10 PM (GMT 0)
142 - not sure what you mean - "Would have helped me make a good decision? No."

Are you saying that with a 70% chance of PCa diagnosis coupled with a 17.7 - 36.9% chance of high grade PCa you wouldn't have submitted to a biopsy???

This tool is not meant to assist in deciding on treatment, but rather deciding on whether to go to the next level of Dx, isn't that all?
Posted 7/31/2013 7:20 PM (GMT 0)
I tried it. I had to put age 55 in the field even though I was 50 at the time.

Results:

Based on the data provided, the person's estimated risk of biopsy-detectable prostate cancer exceeds 75%.

The person's estimated risk of biopsy-detectable high grade prostate cancer exceeds 75%.
Posted 7/31/2013 7:22 PM (GMT 0)
If at that point I had been told that I only had a 27% chance of a high-risk cancer, as opposed to a non-cancer that could be found, but probably wouldn't kill me, I would not have done a biopsy, knowing the circumstances of my life at the time. I was under treatment for stroke-level high blood pressure that at the time was expected to be in line to kill me, so what's a measly 27% ? Of having the "good" cancer?

I don't even remember what a confidence level is. I hated statistics.

With no symptoms that caused me physical issues, and especially if all of the overtreatment bru-ha now had been going on then, I would have used that as a reason to ignore it, and move on.

Posted 7/31/2013 8:07 PM (GMT 0)
I feel the same way 142, I would have ignored it and moved on, even though my family would have been pissed at me.
It was ultimately my choice to do something, but I also feel I was being given the guilt trip treatment for thinking about doing nothing. :-\

Live and learn, I have.
Posted 7/31/2013 8:37 PM (GMT 0)
I don't understand the negative opinions of something like this calculator. If my numbers gave me a 68.7% risk of PCa and a 27.3% risk of high grade PCa, especially if my PSA were above 4, or more likely above 3, I would certainly want a biopsy. I would want a biopsy with numbers lower than that. I understand that members on this board are or have dealt with PCa and I haven't yet, but any tool that helps me make a decision I consider helpful, statistical or otherwise.

By the way, my risk numbers are 15.5% and 1.8%, at age 68. While I am completely against the recommendation to eliminate PSA, I do believe that many men are unnecessarily treated, with loss of quality of life. Of course, this is from all the articles that I have read and obviously not personal experience. I believe that the NCCN guidelines for triggering a biopsy are realistic.

While the men on this board are extremely helpful and knowledgeable about PCa, I do sense a great reluctance to consider anything new that comes out. I joined a couple of years ago so that I could learn what to expect if I had to make a decision in the future.
Posted 7/31/2013 9:32 PM (GMT 0)
I am not giving a negative opinion of the calculator, far from it. I am simply saying that the information, combined with all this overdiagnosis overtreatment bru-ha, would have been something to easily and summarily ignore.

This is where the "fear" that I was trying to describe, and was wrestling a bit with Tony over, comes to play. Not after the fact, fear of what to choose and what side effects it would have, but that immediate fear that makes you do get up and do "something" - anything more than nothing counts.

That "fear" was put into me by a nurse at my GP office. She didn't say get it checked when you have a chance, she called with the names of the best uros, and called me back a half hour later to be sure I was on the phone. I credit her for getting me to do something, not the test or vague discussions of something that was a distant memory of things I might should care about.

Posted 7/31/2013 9:41 PM (GMT 0)
Here are my results, although I had to bump my age to 55.

Estimated risk of biopsy-detectable prostate cancer is 52.3%.
Estimated risk of biopsy-detectable high grade prostate cancer is 15.6%.

Presumably my percentages would have been a bit higher at age 51. I would have definitely sped things along with this info. I had a negative biopsy in 2007, which I considered an indefinite "get out of jail free" card and I relied on that instead of doing my own homework.

BTW, the free % PSA calc didn't work for me since it won't take a number less than 4%.
Posted 7/31/2013 11:47 PM (GMT 0)
I think the calculator is a neat idea in a way, another tool. However, based on what I am seeing here, looks like its almost designed to convince one not to be diagnosed or treated, when almost everyone here so far needed to be.

I ran my info through it, and it showed that I really didn't have to worry. I find that amusing considering how my PC journey has ran so far.

Glad I didn't know about this at the time back in 2008, because I really didn't want to undergo the 3rd biopsy that found my cancer, only did it at the extreme urging of my uro.

This is one of the problems I have of too much dependency on stats. I will say again, I see PC on a patient by patient basis, not as the results of stats and averages.

Was interesting though. I only question its safety, as far as a man yet to make a decision.

David
Posted 8/1/2013 1:45 AM (GMT 0)

142 said...


That "fear" was put into me by a nurse at my GP office. She didn't say get it checked when you have a chance, she called with the names of the best uros, and called me back a half hour later to be sure I was on the phone. I credit her for getting me to do something, not the test or vague discussions of something that was a distant memory of things I might should care about.

142
I had a similar experience with a melanoma on my back. A nurse practitioner said she didn't like the look of it -- even though doctors had ignored it previously. She called downstairs to a dermatologist and insisted he see me immediately. A week or two later I had a large chunk carved out of my back. Nearly 30 years later I'm still alive thanks to her.

As for the calculator here are my numbers
Estimated risk of biopsy-detectable prostate cancer is 73.3%.
Estimated risk of biopsy-detectable high grade prostate cancer is 34.7%.

With those numbers I would definitely have a biopsy. As it tuned out in real life. My biopsy showed Gleason 7 and my post surgery pathology report was T3b.
Posted 8/1/2013 2:09 AM (GMT 0)
Here are my results:

Based on the data provided, the person's estimated risk of biopsy-detectable prostate cancer is 41.3%.

The 95% Confidence Interval for this prediction is 37.2% to 45.5%.
More information about the confidence interval

The person's estimated risk of biopsy-detectable high grade prostate cancer is 5.9%.

The 95% Confidence Interval for this prediction is 3.7% to 8.1%.
More information about the confidence interval


Based on the above, I might not have waited until the next PSA (jump from 4.0 to 4.8) to get a biopsy.

For what it's worth.

Posted 8/1/2013 2:24 AM (GMT 0)
14% chance of high grade cancer....Wrong

how will this catch those Gleason 9s that don't produce much psa?
Posted 8/1/2013 2:27 AM (GMT 0)
Well actually right Jerry,
You sir, unfortunately, were that small group that didn't fare well on the risk factors.

Tony
Posted 8/1/2013 2:58 AM (GMT 0)
I think I would have gone with the biopsy anyway.

Based on the data provided, the person's estimated risk of biopsy-detectable prostate cancer is 51.2%.

The 95% Confidence Interval for this prediction is 46.4% to 56%.
More information about the confidence interval

The person's estimated risk of biopsy-detectable high grade prostate cancer is 10.3%.

The 95% Confidence Interval for this prediction is 6.5% to 14.2%.
More information about the confidence interval
Posted 8/1/2013 4:07 AM (GMT 0)
Purg, you stated "based on what I am seeing here, looks like its almost designed to convince one not to be diagnosed or treated, when almost everyone here so far needed to be" and honestly that's not what I am reading in the results, at all:

A Yooper: Based on the data provided, the person's estimated risk of biopsy-detectable prostate cancer is 42.4%. The person's estimated risk of biopsy-detectable high grade prostate cancer is 9.5%.

Redwing57: Based on the data provided, the person's estimated risk of biopsy-detectable prostate cancer is 36%. The person's estimated risk of biopsy-detectable high grade prostate cancer is 5.8%.

142: Based on the data provided, the person's estimated risk of biopsy-detectable prostate cancer is 68.7%. The person's estimated risk of biopsy-detectable high grade prostate cancer is 27.3%

Southern Comfort: Based on the data provided, the person's estimated risk of biopsy-detectable prostate cancer exceeds 75%. The person's estimated risk of biopsy-detectable high grade prostate cancer exceeds 75%.

TheOldFart: By the way, my risk numbers are 15.5% and 1.8%, at age 68. (He has not seeked treatment as of this point)

Michael T: Estimated risk of biopsy-detectable prostate cancer is 52.3%. Estimated risk of biopsy-detectable high grade prostate cancer is 15.6%.

Bohemond: Estimated risk of biopsy-detectable prostate cancer is 73.3%. Estimated risk of biopsy-detectable high grade prostate cancer is 34.7%.

Steve N: Based on the data provided, the person's estimated risk of biopsy-detectable prostate cancer is 41.3%. The person's estimated risk of biopsy-detectable high grade prostate cancer is 5.9%.

Steven D: Based on the data provided, the person's estimated risk of biopsy-detectable prostate cancer is 51.2%. The person's estimated risk of biopsy-detectable high grade prostate cancer is 10.3%. (Contemplating decisions on treatment)

So then to your point, which of these numbers would cause you to think that "its almost designed to convince one not to be diagnosed or treated?"

Again, I would submit that this is just another tool, and not and "end all" towards a definitive decision.... Certainly the G9 guys would say that!

I just thought, and still feel, this would be an interesting exercise.
Posted 8/1/2013 4:16 AM (GMT 0)
since I am under 55, I guess I am not at risk for PC.

Need to call my doctor about that...
Posted 8/1/2013 7:20 AM (GMT 0)
Mr. WW's results:
Had to bump up age by 6 years.

Based on the data provided, the person's estimated risk of biopsy-detectable prostate cancer exceeds 75%.

The person's estimated risk of biopsy-detectable high grade prostate cancer exceeds 75%.

AND, just for fun, I did one with his numbers that he wasn't told about 5 years earlier.

Based on the data provided, the person's estimated risk of biopsy-detectable prostate cancer is 46%.

The 95% Confidence Interval for this prediction is 41.5% to 50.4%.
More information about the confidence interval

The person's estimated risk of biopsy-detectable high grade prostate cancer is 7.7%.

The 95% Confidence Interval for this prediction is 4.8% to 10.6%.
More information about the confidence interval


We can all see how that worked out.
Posted 8/1/2013 11:44 AM (GMT 0)

Jerry L. said...
14% chance of high grade cancer....Wrong

how will this catch those Gleason 9s that don't produce much psa?

Jerry, you're right on that one. This tool seriously underpredicts my large G9 mess (at 5.8% chance). But mine's also in that category of low-PSA-producing types so some of us would definitely fool the tool.

Based on typical PSA production by tumor volume, mine is only putting out about 1/4 of what it should have for its size. Those Gleason pattern 5 cells don't put out much PSA, if any, and I have a lot of them.

All such tools are built on certain assumptions and populations. One needs to know the underlying assumptions before relying on a tool. Those background items can take some effort to determine. Most studies actually include the entire statistics of their population, and then talk about metrics derived from that "cohort".
Posted 8/1/2013 12:33 PM (GMT 0)
Redwing, excellent points in your last paragraph.

I was hoping everyone would keep things in context with this "tool" - as again, it is not an end-all decision maker!  From their disclaimer page:

"This calculator is designed to provide a preliminary assessment of risk of prostate cancer if a prostate biopsy is performed. Additional clinical information may modify this risk. No specific level of risk is recommended for prostate biopsy and this decision should be an individual choice based upon a physician-patient relationship."

I was/am worried that some would take this exercise as more than what it is intended as..... or even that some might then '2nd guess' where they've gone. 

It's really none of that, but rather simply another tool to provide folks with another viewpoint - no more, no less.

Posted 8/1/2013 12:40 PM (GMT 0)
I don't know how many of you noticed the links on the right side of the calculator that let you adjust for other factors but I played with them a bit, too. I tried to enter the data for conditions that held just before my third biopsy (the positive one) In a lot of cases the questions were difficult to answer crisply. My DRE's for instance: I don't remember any of my doctors saying a DRE result was abnormal. But my urologist, who had already seen (and biopsied) ultrasound 'shadows' on the right during my two previous biopsies, said that while he couldn't feel anything there seemed to be some 'slight firmness' on the right side. I didn't see a choice r for 'slight firmness' in the calculator. Or the finasteride: I didn't like taking it because it squashed my libido and my uro and I had worked out a plan where I took it twice a week (Wednesday and Sunday) which made Tuesdays, Fridays and Saturdays 'good' days to attempt to annoy my wife. So, I was kinda taking finasteride, but less than other guys in the samples on which they based their calculator.

So, here are some of my results given 1) no adjustment, 2) positive DRE, 3) BMI, 4) w/ finasteride

Based on the data provided, the person's estimated risk of biopsy-detectable prostate cancer is
1) 35.6%.
2) 57.7%.
3) 46.6%.
4) 49.9%.

The person's estimated risk of biopsy-detectable high grade prostate cancer is
1) 9.2%.
2) 21.6%.
3) 23.4%.
4) 19.9%.

I played with some of the other calculators but won't report the results since I either don't clearly remember the values they require (I don't remember my free PSA at that time, for instance I think it was somewhere around 12%), or i don't understand the adjustment to be made (number of cores, for instance, what's with that?). I will note that if I entered 16 as my number of cores it gave my risk of any detectable cancer as 29.4% while my risk of high grade cancer was higher at 29.7.

I will add that I had picked out a number for tolerable risk of 16.67% (the risk when playing Russian roulette, as it happens) so whether I would have pulled the trigger on one more biopsy might have depended on whether I was worried about any cancer or only about high grade cancer.
Posted 8/1/2013 1:36 PM (GMT 0)
Thanks for posting, A Yooper.  The results look quite good.

 

Another arrow in the quiver to improve the quality and effectiveness of the physician/patient dialogue about men's health.  More steps in the right direction!

 

 

 

Posted 8/1/2013 3:40 PM (GMT 0)
I find this calculator pretty darn interesting. And when the percentages are higher (and I'm not quite sure the definition of higher..perhaps >25%?) it should certainly motivate someone to take action. But when they're low, it's more of a crapshoot. If I had used this calculator and it gave me 10% odds, I'd probably just continue monitoring my PSA. But at 15%, I'm not so sure.

I'm sure everyone has their own line, but I can see it being difficult for some in certain areas. Still, it's another useful tool as part of an overall approach. I like Casey's comment about being "another arrow in the quiver."
✚ New Topic ✚ Reply
12