The good news is that 98.6% of men with prostate cancer will survive 5 years because of improvements in diagnoses and treatment. Over the last 25 years the advent of widespread use of PSA has caused a dramatic decrease in both the incidence as well as death rates from prostate cancer. Prior to the late 80's and 90's, the death rate from prostate cancer was much higher, close to 40% because many men were diagnosed with late stage disease and metastatic disease.
The use of PSA has caused a stage shifting and most men are now diagnosed with non palpable disease found on annual wellness blood tests which include a PSA.
The bad news is that over the last 2 decades, wide spread use of surgery and radiation for patients with low risk cancer, that may not spread has caused significant distress to many men because of side effects of therapies. The complications and escalating costs from treatment and related side effects has become a contentious issue for insurance companies and society.
The major challenge of screening PSA today is that overdetection and overtreatment leads to unacceptable costs and side effects that impact quality of life. The answer is not to stop detecting cancers but rather to do it more efficiently, cost effectively and treat only those men that need treatment. Men should postpone treatment if they have low risk cancers. If anxiety and psychologic burdens of living with cancer are unacceptable men should evaluate newer treatments that cause less side effects.
Techniques of ‘smart screening’ have been published by experts in the field and are discussed in this website. These strategies can be personalised for individuals based on age, life expectancy, health status and personal preferences. This will reduce over diagnosis. After diagnosis, active surveillance and careful monitoring can be used in men who are thought to have low risk cancer. There is no reliable way to definitively determine which cancers will progress except by monitoring.
Newer techniques of detection and biopsy may reduce under detection and reduce overdiagnosis Men have to know the risks of active surveillance and it may not be appropriate for younger men who are in good health with long life expectancy. For men who cannot handle the anxiety of not knowing if cancer will progress alternative treatments are available that can treat cancer focally with less side effects.
Focal therapy or hemi gland therapy using techniques such as High Intensity Focused Ultrasound (HIFU) are still in their infancy. But they are gaining traction as better methods of imaging and monitoring become widespread. It is just as important to personalise treatment strategies as it is to personalise detection strategies.
In 2012 the United States Preventive Services Task Force (USPSTF) declared that the benefits of routine PSA screening do not outweigh the harms.
There were at least 2 reasons why the USPSTF gave PSA screening a grade D recommendation.
a) A clinical trial comparing PSA for screening versus standard of care (US PLCO trial) showed that routine use of PSA for detecting prostate cancer does not result in reduction of death rates from prostate cancer, compared to standard of care. This trial has subsequently been proved as a flawed study that published a wrong conclusion and created a lot of confusion as to value of screening PSA
b) Routine use of PSA over the last 25 years has resulted in overdetection of a large number of low risk prostate cancers.Many of the do not need treatment because they do not pose threat to the patient during his lifetime. (For further details see Section under Active Surveillance). Most of these low risk cancers until recently were treated with radical surgery and radiation. This resulted in significant side effects of incontinence and impotence. The cost escalation from treatment and related side effects has become too burdensome for men and society.
PSA while an imperfect test should not be abandoned
While PSA is an imperfect test, screening and detection should be separated from treatment and side effects. Abandoning screening grossly oversimplifies the problem. Abandoning PSA screening for all men will take us back to the late 70s and early 80s when death rates from prostate cancer were double what they are today.
During my residency training years in the late 70s and early 80s when PSA was not available, prostate cancers were diagnosed at a late stage by rectal examination or clinical symptoms of urinary obstruction and bone metastasis.The 5 year survival from prostate cancer was 66% in the 70s compared to over 99% today.
Although death rates for prostate cancer have dropped 53% in the last 25 years the benefit is only seen if these cancers are detected early. PSA screening shifts cancer detection from a late stage to early stage. Advances in technology have made treatment of early stage prostate cancer effective and safe. Without PSA we would be back to the era of diagnosing prostate cancers when they are late stage and metastatic (spread to bones).
Treatments for prostate cancer once it has metastasized has not improved much in the last 25 years. In a report in 2014 (CANCER 120, 6; March 2014,p 818–823) researchers at UC DAVIS found that among 19,336 men who developed metastatic prostate cancer in California death rates did not change between the years of 1988 through 2009 because treatment for metastatic cancer had not improved in the past 25 years.
Dr. Marc Dall'Era, urologic oncologist and senior study author, stated “these findings add to the body of evidence about detecting prostate cancer early through PSA testing".
Because PSA testing detects cancer earlier fewer men develop metastatic cancer. Once metastatic cancer occurs death rates are the same as 25 years ago. Newer treatments we have today although costing millions, are not significantly prolonging death rates in men with metastatic prostate cancer. This is significant important information for a man to know when he is considering Active Surveillance”.
Since the USPSTF
In April 2017, the USPSTF revised the 2012 guidelines stating that PSA can be used for early detection of prostate cancer as long as it is a shared decision between the patient and physician after discussion of the benefits and risks of doing PSA. The USPSTF revised these guidelines based on the fact that the European randomized trial of PSA vs no PSA in men showed a benefit of reducing incidence of metastatic disease and death rates in favor of PSA.
Prostate Caner is the most common cancer in US men affecting 1 out of 7 men during their lifetime. The estimated cases of newly diagnosed prostate cancer for 2017 is 161,360. Prostate Cancer forms approximately 10% of cancers in the US and is expected to cause approximately 26,730 deaths in 2017.
Prostate Cancer Facts //
By Perinchery Narayan MD
Globally prostate cancer is the most common cancer in men, with 1.6 million men. In 2015, it was estimated that all cancers increased by 33%, due to aging of the population contributing 16%, population growth contributing 33%, age-specific rates, contributing 4% . Cancer of the lung was the most common cancer and the most common cause of death globally in men. In women, the most common cancer was breast cancer globally with 2.4 million cancers worldwide and also the most common cause of death in women.
Prostate cancer was noted to cause a disproportionally high amount of years lived with disability, secondary to life altering side effects on potency and incontinence due to cancer and treatment related side-effects. The odds of developing prostate cancer between to 0 and 79 years is estimated 1-14 at the global level, and ranged from 1 in 47 men for low-middle SDI countries to 1 in 6 men in high SDI countries.
SDI = Social Demographic Index
JAMA Oncol. 2017;3(4):524-548. doi:10.1001/jamaoncol.2016.5688