Many members of the prostate cancer community have a bone to pick with Prof. Gilbert Welch of Dartmouth College. … Yes, he is one of the leading advocates for the abolition of mass, population-based use of the PSA test to screen for risk of prostate cancer.
However, whatever one might think of Dr. Welch’s views about overuse of the PSA test, you would be wise to read his OpEd published today in the New York Times.
Dr. Welch asks a very simple question: When it comes to medicine and medical care, why don’t we make sure that what we think we know is actually correct? Most of medical practice today is, in fact, based not on what we know, but on what we think we know.
There have been many relatively recent examples from the world of healthcare and medicine which have clearly demonstrated that what we think we know is wrong. Here are just a few of the truly non-controversial ones:
- Throughout most of the lifetimes of anyone on the planet over 60 years of age, we thought that the “normal” temperature of a young adult human being when taken by placing a thermometer under the tongue was 98.6 °F (equivalent to 37.0 °C). This was based on an axiom laid down by Carl Wunderlich in the mid 19th Century. In 1992, Mackowiak et al. decided to actually test this axiom — consequently recommending that 98.6 °F (37 °C ) “should be abandoned as a concept relevant to clinical thermometry,” that 98.9 °F (37.2°C) should be regarded as a “normal” temperature in the early morning and that 99.9 °F (37.7 °C) should be regarded as the upper limit of the normal oral temperature range in healthy adults aged 40 years or younger. In fact, “normal” human temperatures vary significantly, and are known to depend on things like where in the body the temperature is measured, the time of day it is taken, and the age and level of activity of the individual.
- OTC cough syrups don’t work any better than a placebo in treating children (and they probably don’t work better than a placebo for adults either) and yet we consume them in billion dollar quantities every year.
- It is clear that spinal fusion surgery conducted to relieve back pain does not, in the majority of patients, work any better than physical therapy. Again, however, billions of dollars are spent every year on hundreds of thousands of these surgical procedures. Surgeons and patients both think that what they know is more accurate than what we really do know.
And of course examples like these don’t even touch such issues as whether vaccinations cause autism and whether cell phones cause brain cancer — both of which have been studied to death, with no good evidence to support either belief, but that doesn’t mean we are willing to accept that our beliefs aren’t true.
If we really want to be able to state, with accuracy, that “America has the best health care system in the world” (a recurrent claim based on absolutely no evidence at all), isn’t it about time that we set out to determine whether what we think we know is correct and to stop doing things that are very clearly wrong? At least we have managed to accept that things like prefrontal lobotomy and electroshock therapy are inappropriate ways to treat depression and other mental disorders! And someone even got a Nobel prize for the discovery of prefrontal lobotomy!
Much of the diagnosis and management of prostate cancer is still based on what we think we know. Think about it.
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Re what we don’t know. … I have been diagnosed with prostate cancer staged as Gleason 3 + 3 = 6. I have read that most patients with Gleason 6 cancer will be a Gleason 7 by the time we get into surgery. My doctor, who is not a stupid man, says, “No. If you are diagnosed as 6 you will still be a 6 eight months from now, unless there is tissue classified as Gleason 7 that has not yet been discovered through biopsy.”
Dear Joseph:
Your doctor is correct. In general, men classified as Gleason 6 will not have progression of their disease over an 8-month period. However, there is always the possibility that a 12-core biopsy will “miss” tissue that has a different grade during the biopsy process. It is therefore possible that, in the pathological examination of prostate tissue removed at surgery from a man originally diagnosed with Gleason 6 disease, some Gleason 7 tissue will be found. The exact frequency of this finding is much debated, but it is certainly reasonable to think that this will happen in about 25% of patients diagnosed with Gleason 6 disease who go on to have surgery. The vast majority of these men will still have a perfectly good oncologic outcome after surgery because even the Gleason 7 cancer will have been entirely confined to the patients’ prostates. However, there are exceptions to every rule.
Thank you for your reply. I was diagnosed in April of this year with Gleason 6 disease. On May 27 I had severe pain below the belly button area. I was given an antiinflammatory medication for this pain, and it went away after several days. It is now late August and the pain is back, only continuous for a week and counting.
I’m on tramadol and Naproxen. What can I expect over the next several months? My operation is scheduled in late October. Would this be in the lymph nodes or the intestine.
Regards
Joe Mac Isaac
The distinction between what we know and what we think we know is growing in popularity amongst scientists and philosophers. Last month I read an entire book on cosmology organised around it. In any field where too little is known to be true, the distinction is helpful, if not necessary for clear thought in such fields. This article is an excellent exposition of why the distinction must often be kept in mind. I posted it on my Facebook page. Thanks.
“I know” that I shouldn’t have listened to all the media, etc. … that provided confusing information about the PSA. “I know now” that I should have gotten my PSA every year starting at age 40. I did the 40 part, but waited til 44 for a recheck. “I know now” I have a Gleason 9 with bone mets.
“I know” I am the exception … but “you know”, it could have been prevented.
Jerry:
I know that your PSA was 4.3 when you got diagnosed at age 44 … but out of curiosity, what was it when you got tested at age 40?
Dear Joe:
I don’t think that your lower abdominal pain is necessarily associated with the prior diagnosis of prostate cancer at all. Lower abdominal pain is not a “usual” symptom of prostate cancer. You need to discuss this with your doctor. However, one thing that is certainly possible is that your lower abdominal pain is associated with worry about your cancer diagnosis rather than the actual cancer.
0.75 ng/ml.
Jerry:
Yup … You’re right. Based on that PSA level at age 40 you were (just) definable as being at elevated risk even then and so should have started to get annual PSA tests. However, even that would not have guaranteed a cure. In some men the cancer escapes the prostate very early and grows outside the prostate very slowly over time. We have no idea why this happens (as yet), but we do know that there is a subset of men who get early micrometastatic disease and are therefore inherently incurable (with any form of therapy currently available).
I would encourage all men at age 40 to get a baseline PSA test. If necessary – yearly PSA tests after that. Stay on top of it.
My problem is with the mixed messages that come across the news, government agencies, and other leaders among the prostate cancer community. Other “Jerrys” that are 40, 41, 42, etc., see the news and they hear that the test does more harm than good, etc. Guys don’t need another excuse, they do very well by themselves at staying away from doctors and their health without mixed messages.
I would imagine a sampling of 1,000 guys between 38-43 don’t even know what a prostate and PSA are. They should.
How about what we do know … that some 30,000 men die of prostate cancer each year … and that many of those men had high-risk disease and may have lived longer or died of another cause if diagnosed early.
Most arguments against mass screening fail to recognize the benefits to men with high-risk disease, nor do they balance the benefits to those men to offset the acknowledged cost of over-treatment, not to mention the cost of advanced treatment to high-risk men, their pain, and their economic loss.
Rick … No one would argue with the two facts in your comment, about the 30,000 men who die each year and that many of those men are diagnosed with high-risk disease … However, …
I feel obliged to point out that this hasn’t actually changed significantly since the introduction of widespread use of the PSA test. Back in the late 1980s, about 30,000 men died each year, and many of them were being diagnosed with metastatic disease.
There is a serious argument here that widespread use of the PSA tests, along with the earlier use of currently available forms of localized treatment has not, in fact, significantly affected the prostate cancer mortality rate, which further implies that we aren’t effectively treating men who present with high-risk disease at all.
Hello Mike — correct me if I’m wrong, but I believe deaths from prostate cancer around 1990 were 36,000+; this year that number is projected to be 28,000+ — that is a reduction of more than 20%.
We can argue causation, whether it be screening leading to earlier detection or better treatment, but note this is the same period over which screening has been widely introduced. If we asked a statistician to plot screenings against deaths, I suspect the correlation factor would be high!
The issue at hand is that screening arguments rarely if ever focus on high-risk men. Admittedly most who argue against screening accept that men exhibiting high risk factors (race, family etc) should be screened but there are all to many men with high-risk disease who never exhibit these risk characteristics.
PS: I look forward to meeting you in DC early next month.
I’ll be the first to admit that I don’t know the numbers that great. But with the above numbers, you would think that the US population in 1990 would be different than 2012. So, more men and yet a reduction of 20%. Seems significant.
:-) LOL
I have been referring to “medical beliefs” for some time now in discussions, especially where a point is being made that “there are no studies which demonstrate this or that.”
In too many circumstances there are no studies of that sort to support “medical beliefs”.
Here’s an on-point article that appeared in today’s (8/24/12) Medscape Medical News: “Prostate cancer survival improved after PSA introduced in US.”
PSA screening along with a DRE is the best we have for early detection of prostate cancer. Start screening at age 40 or earlier based on family history is my advice. I am not a MD, I am a patient.
Many opinions but few facts!
The 5-year survival rate for prostate cancer improved from 30.4% in the period 1975-1979 period (survival rate of 69.2% before PSA screening) to 99.6% in the period 1990-1995 (after PSA testing began in 1981 for recurrence) — based on November 2010 SEER data submission posted to the SEER web site in 2011.
FACT: PSA and DRE screening saves lives!
The debate is quality of life after treatment which is also a published fact.
Men need to screen for prostate cancer and if cancer is detected research every treatment option to make an informed choice.
Best Wishes,
Fred Kinder
Dear Fred:
You’re completely correct … many opinions but few facts …
The SEER data you refer to is absolutely accurate. There has been a massive improvement in 5-year survival of men diagnosed with prostate cancer over the past 40 years (from the time of their initial diagnosis). That is a fact. However, in 1975-79, about 90% of the men being diagnosed with prostate cancer were being diagnosed with extensive, symptomatic, metastatic disease, whereas today nearly 90% of patients are being diagnosed with symptomless, localized (and often indolent) disease. In other words, these 5-year survival data are based on a comparison of apples to melons. Please look up information on stage shifting and so-called lead time bias for futher information.
With regard to the use of PSA testing and DREs. These tests only have any value in testing for possible risk of prostate cancer. As screening tests for clinically significant prostate cancer for most men (as opposed to tests for risk in men who may well be at risk), their value is unproven. Sorry. It is not a fact that widespread use of PSA screening (as opposed to selective testing of individuals) has benefits that outweigh the risks. That is very much a matter of personal opinion at this time, which is exactly why it is so controversial, just like the American political landscape.
Having said that, I would agree with you that, despite the above, the combination of PSA testing and DREs is indeed the best we have today to assess risk for clinically significant prostate cancer, and that men who are concerned about that risk in any way would be wise to get baseline PSA data in their early 40s because this will help them to be aware of their personal risk (if their PSA is > 0.7 ng/ml at that time according to people like Vicers and Lilja). There are also several other known risk factors for clinically significant prostate cancer — starting with being of African American or African Caribbean ethnicity or having a significant family history or prostate cancer (which does not mean just a single family member diagnosed with low-risk or very low-risk, localized disease some time since the initiation of widespread use of the PSA test).
Dear Sitemaster,
Thanks for your comments and the supplemental facts which illustrate the life saving benefit of PSA and DRE screening. Before widespread screening as you pointed out with facts:
“However, in 1975-79, about 90% of the men being diagnosed with prostate cancer were being diagnosed with extensive, symptomatic, metastatic disease, whereas today nearly 90% of patients are being diagnosed with symptomless, localized (and often indolent) disease. In other words, these 5-year survival data are based on a comparison of apples to melons. Please look up information on stage shifting and so-called lead time bias for futher information.”
As you pointed out, stage shifting illustrates the factual benefit of widespread PSA and DRE screening. Before screening 90% of men suffered from a miserable painful end of their life cycle. Today 10% or less are diagnosed with extensive, symptomatic, metastatic disease.
We can agree the quality of life for many men has suffered because of high-risk treatments, over-treatment (driven by doctors and patients). Fact: PSA and DRE screening is a benign tool indicating risk that may support further investigation.
My response, to the USPSTF draft and/or those who support their screening prostate cancer position, is based on facts and logic:
The USPSTF study and conclusion is “Simply a poor investigation of the topic and conclusion without reasonable due diligence.”
PSA and DRE screening did not reduce the quality of life of men. Doctors screen patients that have no benefit from screening and treatment, patients request screening and treatment when their life cycle will have no benefit and quality of life is at risk.
Men benefit from making choices based on knowledge supported by facts. Screening is for men who will benefit (a grey area and complex) from treatments that offer high disease control with low risk to quality of life. The USPSTF study did not consider the SEER facts including “stage shifting” The study did not take into consideration the increase life of our life cycle. The USPSTF study did not consider the lowered incidence of extensive, symptomatic, metastatic disease.
In my “opinion” this article and the facts support PSA screening as a tool as part of a “decision tree”
Men must make informed choices!
Regards,
Fred Kinder
Dear Fred:
(1) PSA and DRE testing are indeed benign … if you don’t ever go on to get an unnecessary biopsy. Unfortunately all men have to have a biopsy in order to be diagnosed with prostate cancer. Biopsies are not benign … post-biopsy infections actually lead to death in some men every year, not to mention a significant rate of hospitalizations and other problems. We know that tens if not hundreds of thousands of unnecessary biopsies are carried out every year … However, we don’t know that they are unnecessary until after the event. Catch 22.
(2) Using a decision tree approach to determine (a) whether you actually need a PSA test and a DRE in the first place and then (b) what to do about it when you get the result is entirely approrpriate … But that is a mechanism for risk-based testing of individuals. It is not “screening,” which is a mass, population-based process that ignores initial risk. I am entirely in favor of decision trees of this type for the simple reason that it takes account of initial risk and doesn’t just assume that all men need annual PSA tests.
(3) The USPSTF recommendation has never rejected the idea that some men at higher risk levels may need testing. All it has ever said is that there are no data to support widespread, population-based annual screening of all men over age 50. With that single point, I am in complete agreement.
(4) You are correct … Each individual man needs to make decisions based on facts. The problem is that there is no agreement on those facts … because some things being presented as “facts” are still just opinions.
:O)
Dear Rick:
The way in which mortality rates have been estimated in America has changed multiple times between about 1980 and today, and we can’t really compare apples to apples. On top of that, most epidemiologists will tell you that prostate cancer as a cause of death on death certificates has also been a moving target.
I will agree with you that one can pick estimates that suggest a decline in the number of deaths from prostate cancer between about 1980 and 2008 (the last year for which “accurate” estimates of mortality are available, as opposed to projected estimates). However, no one can tell me with any degree of accuracy what the real number of prostate cancer deaths has been in America each year for the past 30 years, which is why many people tend to use the words “about 30,000″ (just as you did above).
When you pick deaths in 1990, which is the year with the highest ever estimated number of deaths, and then compare it to this year, you can make a good argument, but it is not a “factual” argument. Do I suspect that the number of age-adjusted deaths per 100,000 population really is falling very slowly? Yes I do. However, I still think that many (and perhaps even most) of the men who actually die of prostate cancer have a form of the disease that is commonly incurable at the time of diagnosis — even when it is diagnosed early, and I am less than certain that PSA testing makes a major difference to their chances for a cure.
With respect to your comment about appropriate frequent testing (not screening) of high-risk men, Vickers and colleagues have been pointing out for several years now that a man with a PSA > 0.7 ng/ml in his 40s is a higher-risk patient, and we have most certainly also been emphasizing this. Thus there is a way to identify many men who are at higher risk early. I would advise any man to get a baseline PSA taken in his 40s today … but as a risk monitoring tool. As you well know, I do not feel that annual, mass, population-based screening for the majority of the male population of America can be justified on the basis of any available data, but I freely admit that that is something that I think that I know, because I can no more prove it than you can prove the opposite.
Again … what do we really know and what do we just think that we really know? It is critical to appreciate the distinction.
Mike:
I actually had anticipated this reply, and would respond as follows:
Ask a statistician to run a regression line through the mortality rates over the past 20 years, and I suspect you will see a gradient producing a decline of close to 20% over the 20 years. Perhaps one of our better stats readers can do that and report.
As to measuring the quality of the date, I am not sufficiently knowledgeable to respond other than to suggest many much better qualified researchers depend on this same data.
Joseph MacIsaac: “I was diagnosed in April of this year with Gleason 6 disease.”
Is your stage T1 and your PSA < 10? If so then you are at a low-risk stage and I wouldn't be in any hurry at all to get a prostatectomy.
I have a prostate that is 127 cc volume. Normal is below 40 cc. My tumor is 20% of the mass of the prostate, so it is quite large. My PSA is 4.9 ng/ml.
I checked with the Cleveland Clinic on Bay Street in Toronto and they couldn’t do their procedure as the prostate was too large. I have had a terrible stabbing pain in that area and discomfort. I have had prostatis since my early years. All the doctors I have talked to recommended that I should have the surgery. I am a 69-year-old man. Joseph mac Isaac.
Dear Joseph:
I have no idea what procedure you are saying that the Cleveland Clinc told you they couldn’t do, but large prostates are difficult to impossible to treat with brachytherapy, high-intensity, focused ultrasound (HIFU), and cryotherapy.
Like the doctors you have spoken too, I would note that radical surgery will not only remove any cancer. It may also be able to resolve your chronic prostatitis. I know no other form of treatment that can have that effect. Have a look at this link on the effects of radical prostatectomy as a treatment of last resort for severe, chronic prostatitis.
Dear Joseph,
My comment was only intended to apply to men whose problem was just prostate cancer. There are many prostatectomies done for reasons other than potentially metastasizing prostate cancer. Sorry for your condition in any case.