T

hat popping sound you may have heard on Tuesday was made by urologists opening the champagne bottles they had chilled in anticipation of the United States Preventive Services Task Force (USPSTF) upgrading its recommendation about PSA screening for prostate cancer from a D (the harms outweigh the benefits) to a C (it’s an individual decision).

Much like a teacher changing a dissatisfied student’s grade from a D to a C — and only after much complaining — the new guidelines should hardly be construed as a ringing endorsement. PSA screening remains a difficult decision for healthy men and their doctors.

The test measures the amount of a protein called prostate-specific antigen (PSA) in the bloodstream. A PSA level above 4.0 nanograms per milliliter of blood has been used as the traditional cutoff to suggest the possibility of prostate cancer (though experts could easily have picked a 5.0 cutoff many years ago). Screening means testing healthy individuals to see if they might have hidden cancer.

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The data on which the USPSTF based its new recommendation for PSA screening is similar to the data it used for its prior recommendation in 2012. No study has shown that the test saves lives or improves the quality of life. It does not reduce mortality or extend survival in any randomized trial to date, nor when all studies are combined together. Let me say that again: There is no proof that PSA screening extends your life, improves the years you have, or reduces your risk of dying.

A large European study showed that the test reduces the risk of dying from prostate cancer by about 20 percent or by 0.11 per 1,000 men per year of follow-up, though this benefit was not seen in all nations. In Finland, for instance, there was no benefit, while there was a larger one in Sweden. Unfortunately, data from this study are not shared with other researchers. That is troubling given recent high-profile reversals with data sharing and reanalysis, including other PSA studies. For matters of public health, it is not OK to keep data secret. We have to put all the cards on the table.

A large American trial of PSA testing, published in 2012, has made its data widely available. This trial showed no benefit from screening but — thanks to data sharing — we know the trial wasn’t perfect. The group assigned to PSA screening was tested appropriately, but some men in the group assigned to no screening had their PSA tested. Why? It was difficult to prevent men in the US from getting a PSA test because, quite frankly, our nation was punch drunk on the test. We were so enthusiastic in those years that it wasn’t possible to do a fair trial in the US. The lesson here is that it is hard to test something in medicine that has already been broadly implemented.

PSA screening still has all the harms we hear so much about: false positives, overdiagnosis — which means treating a cancer that would otherwise not cause harm — and the side effects of diagnosis and treatment, including incontinence, impotence, and even death.

In my mind, the greatest misconception about the test is that we say it “saves lives” when that is uncertain. PSA testing reduces the risk of dying of prostate cancer, but there is no evidence it reduces the risk of dying.

How can we make sense of this difference? A useful analogy is right under our noses: our teeth. Adults have 32 (or 28 if your wisdom teeth are gone), and most of us want to keep every last one.

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Prostate cancer accounts for 2 percent to 3 percent of deaths among men, or roughly 1 of 32 deaths. PSA screening isn’t perfect and doesn’t provide any information about other possible causes of death.

PSA screening, then, is like a dentist applying a sealant to one of your 32 teeth, and that sealant reduces the risk of losing the treated tooth by 20 percent.

What about the other teeth? Many experts believe the sealant has no effect — not positive or negative — on the other teeth. Others, including me, believe that the sealant slightly increases the risk of losing one of the untreated teeth, which would offset the small 20 percent benefit for the treated tooth.

Overdiagnosis and overtreatment are common with PSA screening — the USPSTF says it happens in 20 percent to 50 percent of men diagnosed by screening — so even small harms may counteract any benefits of screening. For instance, some treatments for prostate cancer, such as radiation therapy, can increase the risk of getting a second cancer.

Using the teeth analogy, here’s the best-case scenario for PSA screening: It modestly strengthens one tooth. The worst-case scenario: It slightly weakens other teeth.

Despite all of the studies to date, we have no evidence to know which of these two scenarios is true. Instead of being honest about this fact, and letting people decide, the medical profession has brushed it aside and blindly promoted screening based on rhetoric and empty persuasion. Well-meaning celebrities like Ben Stiller haven’t helped.

As an oncologist who cares for cancer patients, I have no desire to trivialize cancer, and I know that prostate cancer is far worse than losing a tooth. So I use the analogy reluctantly, hesitantly, and only because I think it helps us think more clearly about screening. There is a big difference between the phrase “reduces the risk of dying from prostate cancer” and the phrase “reduces the risk of dying.” Men must understand the difference to make an informed choice.

The USPSTF’s C recommendation for PSA screening means the decision should be individualized, something I support. Prostate cancer screening may be OK for some men — those who are more tolerant of risk and uncertainty — but it is surely not right for others. As for African-American men, or men with a family history, the USPSTF provides caution that there is no good evidence to show greater benefit from the test, and it is possible the harms are greater in these groups. PSA screening is OK only if doctors are honest about what the test can and cannot do.

PSA screening has real harms. It reduces the risk of losing one of your 32 teeth by 20 percent, but we have no idea what it does for the other 31 (it may weaken them). For some men, the benefit and uncertainty might be worth it. But for others it may seem like so much for so little.

Vinay Prasad, MD, is assistant professor in the Division of Hematology Oncology at Oregon Health and Science University and the author of “Ending Medical Reversal.” The views expressed in this article are the author’s personal opinions and do not represent those of OHSU.

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  • I would like a suggestion or opinion as to what I can do for my husband’s prostate cancer. He had a biopsy last Aug. and within three days he was admitted to the hospital ICU with a very high fever and a serious infection. Additionally, he was diagnosed with prostate cancer (Gleason 9). Since that time he has had 3 additional hospital admissions all related to the infection. I have had to infuse him with antibiotics 3 times for a month, then 18 days and lastly, 2 weeks. He also was catheterized for about 6 weeks and had 11 days of radiation in Dec. It was decided by his urologist to not continue with the radiation because this was what caused him to have to be catheterized. As of now, he is receiving hormone shots and nothing else. Any recommendations would be greatly appreciated. Psa is being kept low but it is certainly not a cure. Thank you.

  • This perspective unfortunately glosses over another major concern with prostate cancer, which is the pain and disability metastatic disease can cause. Having walked many patients through the end of their lives with metastatic disease, I think the screening decision is more complex and difficult than simply whether screening saves lives.

    A recent study in the NEJM showed that watchful waiting did not reduce death, but did increase the risk of metastases. The science of screening for and treating this disease is far from complete.

    Decisions in this difficult situation should be made through robust collaborative shared decision making by doctors with patients, so the patient’s can be educated about the risks, benefits alternatives and unknowns for screening, diagnosing and treating the disease, and their individual goals and values can be explored and accommodated.

  • Dr. Prasad’s comments that there is no evidence that PSA screening reduces the overall risk of death are misplaced, as it would be almost IMPOSSIBLE for such evidence to be provided given the sample sizes of the available studies. If you do a power analysis, you will find that given the large percentage of men in this age range that you would expect to die from natural causes during a 10 or 15 year follow-up period, you would need a sample size of 4 or 5 million men in a randomized control trial to have some reasonable power of detecting a change in the overall death rate of the size of the change in the prostate cancer death rate in the European study. We know that such a study will NEVER be done — there will NEVER be a RCT with a sample size of 5 million for prostate cancer screening. Therefore, Dr. Prasad is asking for evidence on overall death rates that can never be produced in the real world. In fact in the European study, the treatment group which was offered screening in fact had a lower overall death rate than the control group, by about twice the magnitude of the decline in prostate cancer deaths. But given the sample sizes, this estimated decline in overall deaths was statistically insignificantly different from zero, as well as from much larger magnitudes.

  • Thank you for this. Do you have any comment on the increasing consensus that even if you are diagnosed with prostate cancer, you are more likely to be advised not to do anything about it? Why would we want to be diagnosed with a disease, only to be told not to treat it? And “watchful waiting” was largely not a thing when this data was collected. That by itself might change the answer.

  • If patients were getting complete and proper information on which to base their decision, this recommendation would be nearly ideal. There is a March 2017 article by Turini et al and it includes this partial sentence: “Among 217,053 men in the analytic sample, 37% were told about only advantages of PSA screening compared to 30% of men who were advised about both advantages and disadvantages.”

    Additionally, the USPSTF’s own Recommendation document includes a Table that shows that, based on ERSPC data, of 1000 men screened, 1-2 would avoid death by PCa. Not exactly compelling!

    • I found the Table. Based on data from the 13 years of this study, for 1000 asymptomatic men aged 59-69 screened, there were:
      240 positive PSA tests
      200 would have 1 or more biopsies
      100 would be diagnosed with prostate cancer
      3 men would avoid metastatic disease
      2 avoid death by prostate cancer
      200 men died of something other than prostate cancer

      Now, if you are one of the 2 men who would avoid death by being screened, you’ll appreciate having the screening test.

      Finally, if you have a family history of prostate cancer OR if you have/had any symptoms – then this info does not pertain to you (go get tested).

  • Beware of the PSA test! Last year I was given one without my knowledge. I thought I was just having my cholesterol tested. The doctor told me my PSA level was very high and I should go to a urologist and have a biopsy. I immediately read the work of Dr. Prasad and Dr. Kenny Lin and others. This convinced me of the serious failings of the test and the serious disagreement in the medical community over it. I decided I wasn’t doing anything when so many highly respected doctors expressed such grave doubts. However, due to much nagging from my wife I went to another doctor and had another test. The result this time was perfectly normal and so much lower than before as to be comical if it hadn’t been for all the worrying it caused for a number of months. Was the discrepancy due to an infection? Bad lab work? Who knows? And that’s the whole point. I shudder when I think about what would have happened if I had gone to a urologist as originally recommended.

    • May I suggest you use the recent test value as a baseline? Get another test in 1-2 years (sooner if you have symptoms), and use the information to see if there if there is a significant trend. If the test next year is higher than it is now (bear in mind that PSA is age-related), then get another test in a couple of months. If the values are moving slightly higher, you may need to chat with a Doc. If they are rising greatly, get to a Doc. If they remain near zero, or at least very low (less than 1 ng/ml perhaps?), then rest easy and move on and enjoy your life.

  • As a survivor of prostate cancer I have to take issue with Dr. Prasad’s arguments against the PSA test. From my perspective the PSA test does no harm and in fact can provide life saving information to the patient. In my case my PSA results were .9 every year until age 62 when it jumped to 3.0. My physician speculated that it could be prostatitus and prescribed a 30 day course on antibiotics. When the test was done again it jumped to 3.3 and a followup test had it at 3.6. At that point a biopsy was recommended and the cancer was discovered. I opted to have my prostate removed and have been healthy since then. Without the PSA test I would most likely have been looking at a much different outcome. People need all the medical information they can get to make informed decisions about their treatment.

  • Recommending the men do not get tested is at least irresponsible, likely incompetent, & possibly criminal. Having been flagged with rising PSA, with a father who had prostate cancer, & a mother with breast cancer, I had a biopsy that showed cancer. I followed that up with a 2nd opinion & multidisciplinary consultation at Johns Hopkins. That review showed a more serious cancer than the earlier pathology evaluation.

    During that consultation, it was clear that surgery was my only realistic option. I am 53 years old. Radiation was not an option because of several factors. After surgery, my pathology showed me as cancer free, but the pathology also showed the cancer to have been worse than suspected through biopsy.

    I am happy to have had the PSA test, to be diagnosed early with a potential fatal disease. My diagnosis & surgery was my Christmas present for 2016. I could not have received a better gift.

    I still need to test my PSA to ensure the cancer does not return. My 90 day test shows PSA as 0, as not to be found. I pray & have faith that this will continue, & I thank my doctor’s for testing me & saving me from cancer.

  • I have a rapidly rising PSA. Biopsy revealed cancer throughout the prostate (Gleason 7; 4/3, 4/3, 4/3. I have scheduled a robotic prostatectomy. I am healthy and 74. Does your article mean I am making a bad choice?

    • My initial PSA was rising, & my biopsy showed as 3+3, with a small area of possible 3+4. The Hopkins evaluation showed more as 3+4, with perineural invasion. My post-op pathology showed additional/increased finding of 3+4, & showed seminal vesicle invasion.

      I had a robotic prostatectomy at Hopkins. I am at 3 months into my recovery. So far, I am ahead of schedule for recovery. I am pleased with the journey to date, & with my surgery & support team.

      Good luck to you in your journey, & God bless.

    • Randall…Get 2nd opinions, & get expert advice from wherever possible. I chose to go with a top 5 prostate cancer team. That assisted me with the decision, & with being confident as to my direction.

      I cannot speak for you, of course. Our situations are unique. I am 10 years younger, & there are other individual factors as well. Just get the best team that you can to support your decision making, & for any specific actions.

    • Rapidly rising is a sign that something is amiss, and assuming that you and your Doc have ruled-out prostatitis or BPH, then you seem to be a good candidate for prostatectomy. The key is that you said ‘rapidly rising’.

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