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THE USE OF "PSA" IN PROSTATE CANCER SCREENING

The US Preventive Services Task Force (USPSTF) has announced that it has a draft amending its recommendation to use PSA for the early diagnosis of prostate cancer.

In 2012 recommended not to use it in any age group. In this draft of 2017 suggests not to use it in men of 70 years and more, nor in men under 55 years, but use it in men of 55 to 69 "individualizing each case"; That is, explaining the pros and cons to each male to achieve informed consent before requesting the PSA determination.

Below is a summary of the information the USPSTF suggests about the pros and cons, according to clinical trials conducted in Europe and the United States. That is, according to figures from the provision of services of the highest quality, under experimental conditions (generally much better than in the actual conditions and practices of the daily clinic):

If two groups of 1,000 men are compared for 11 years and one is regularly assessed the PSA (intervention group) and the other non (control group):

   1. Among PSA screened 5 will die of prostate cancer (6 in the control group)

    2. Among the PSA screened 210 will die for all causes (210 in the control group)

    3. Among PSA screened there will be 240 with high PSA suggestive of cancer

    4. Among the 240 PSA screened with high PSA numbers suggestive of cancer, the biopsy will confirm the diagnosis of malignancy in 100 (in 140 the high PSA will have been a false positive and undergo biopsy problems - anxiety, Pain, bleeding, infections including septicemia - with no benefit)

    5. Of the 100 diagnosed cancer, 80 will be treated with surgery and / or radiotherapy

   6. Of these 80 treated, 3 will benefit because in 77 does not change the final result (the cancer was indolent and would not kill, or was so aggressive that kills even after being treated)

   7. Among the 80 treated, at least 60 will have major complications such as sexual impotence and / or urinary incontinence

   8. In total, up to 50 of the 100 diagnosed with cancer will suffer the consequences of such diagnosis and the consequent treatments and complications in vain because their cancers would never have threatened their lives (overdiagnosis).

The USPSTF considers a "risk group" to those who have relatives with prostate cancer, but since the PSA determination leads to a greater likelihood of a diagnosis of prostate cancer (incidence increased by 25%), the recommendation to consider group of men who have relatives with prostate cancer only contributes to creating an ever-growing snowball of men diagnosed with prostate cancer (with no impact on overall mortality). In the end the "normal" for humans will be having family members diagnosed with prostate cancer.

In summary:
With the best possible assistance and organization (in clinical trials) the regular PSA determination for 11 years

    1 / decreases the risk of dying from prostate cancer by 0.1% (from 6 per thousand to 5 per thousand),

    2 / does not reduce total mortality (one death per one thousand for prostate cancer is avoided, but no benefit in overall mortality, ie with the same probability of dying),

    3 / serious damage occurs, such as 58% false positives (with no benefit to compensate for biopsy damage), 75% of those treated with sexual impotence and / or urinary incontinence, up to 50% of overdiagnosis and contributing to increase in false the "family risk" of suffering / dying from prostate cancer.

1http: //jamanetwork.com/journals/jama/fullarticle/2618352

-to evaluate  a prostate cancer screening program the basic information needed is: 1/ prostate cancer specific mortality, 2/ total cancer mortality, 3/ quality of life of those screened and 4/ all-cause mortality
-the outcome or prostate cancer screening programs is very poor as the quality of life is worse in screened men, and as all-cause mortality does not change
-that is: you suffer for nothing
-if you have 55 years, with PSA over the next 10 to 15 years, you can expect a reduction of prostate cancer mortality from 0.6% to 0.5%; you have a 25%  chance of having a positive PSA test result at some point during  screening that will likely require a biopsy with possible adverse  effects of pain, bleeding, and infection; you have a 10% chance of being diagnosed with prostate cancer, with a  substantial proportion of these cancers (20%-50%, based on the trials)  unlikely to grow or spread (overdiagnosis). About 65% of men diagnosed with prostate  cancer are treated with surgery or radiation soon after being diagnosed.  An additional 15% have surgery or radiation treatment later, after  their cancer is found to have progressed under active surveillance; 75%  of all those treated experience impotence, incontinence, or both as a  result of these treatments.
-worse, all these numbers refer to RCT not to daily practice; so all these numbers are  the best; in practice quality usually is not so high
-the  prostate cancer screening programs increase the number of diagnosis of prostate cancer, so if you recommend it you increase the "army" of survivors in false (overdiagnosis) to prostate cancer AND, worse, you increase the "family risk" of having prostate cancer, and the "family history of prostate cancer" creating a snow ball that finally will include all men in the Humanity
-a few references:
Bibbins-Domingo K, Grossman DC, CurrySJ. The US Preventive Services Task Force 2017 draft recommendation statement on screening for prostate cancer. An invitation to review and comment. JAMA April 11, 2017. doi:10.1001/jama.2017.4413
Gigerenzer G. Full disclosure about cancer screening. BMJ 2016;352:h6967.
Prasad V. The new recommendations for prostate cancer screenings are a bad deal. https://www.statnews.com/2017/04/11/psa-screening-prostate-cancer/
Gérvas J. Ovarian cancer screening: could you recommend it? No. Evid Based Med. 2016. 10.1136/ebmed-2016-110385.
Prasad V, Jeanne Lenzer J, Newman DH. Why cancer screening has never been shown to “save lives”—and what we can do about it. BMJ 2016;352:h6080.
Saquib N, Saquib J, Ioannidis JPA. Does screening for disease save lives in asymptomatic adults? Systematic review of meta-analyses and randomized trials. International Journal of Epidemiology, 2015, 1–14 doi: 10.1093/ije/dyu140.
Philipp Dahm, Molly Neuberger, Dragan Ilic. Screening for prostate cancer: shaping the debate on benefits and harms[editorial]. Cochrane Database of Systematic Reviews 2013;(9): 10.1002/14651858.ED000067 http://www.cochrane.org/CD004720/PROSTATE_screening-for-prostate-cancer