Advances in Testing for Prostate Cancer

When I was 10 years old, my mother lost a close friend to cancer.  I was too young to know anything about serious illness, but when I asked her why her friend died, I remember her saying, “If only they had caught it sooner, maybe his life could have been saved.”  Unfortunately, in the 1960s early cancer detection was just a pipe dream.

 

The Advent of PSA

In the 1980s everything changed, at least for men with prostate cancer.  A simple blood test was discovered called PSA.  If an abnormal PSA test was detected, it was followed immediately with another new technology called the “12-core random prostate needle biopsy.”  Using this new “one-two punch,” prostate cancer could be consistently found at a curable stage.  All of a sudden, a deadly killer could be detected before it spread, making cures a common occurrence for the first time.  The excitement was huge and PSA testing and random biopsy became the norm for men over 50.  In fact, PSA screening became so mainstream it was considered medical malpractice not to do it.

PSA Leads to Aggressive Therapy

Throughout the 1990s, due to aggressive PSA testing and the routine use of random needle biopsies, the number of men diagnosed with prostate cancer ballooned from 100,000 a year to over 200,000.  Back then, the doctors assumed that all these men had a deadly disease, so they recommended aggressive treatment with surgery, radiation or hormonal therapy to everyone.  If a man was diagnosed with prostate cancer, he was going to be administered serious treatment.

What if Not All Cancer is Aggressive?

Toward the end of the 1990s, some experts started to detect some inconsistencies in the medical statistics. Even though radical therapy was being given to twice as many men with prostate cancer, there was only a slight improvement in survival.  What was wrong? After careful analysis it was finally realized that many forms of early-stage prostate cancer are actually harmless.  They will never metastasize. Intervention—with all its side effects— has no impact on mortality rates.

Trying to Close Pandora’s Box

Due to this horrible misjudgment of prostate cancer committed by the medical community, between 1987 to 2007, over a million men underwent unnecessary radical treatment.  Worse still, even though we can now distinguish between harmless and harmful prostate cancers, hundreds of thousands of men continued to receive unnecessary therapy from 2007 to the present.  The problem is that many people can’t come to terms with the concept of a harmless cancer.  The corrosive nature of the word “cancer” twists the minds and emotions of both doctors and patients. It seems “harmless cancer” is about as easy to understand as “friendly racist” or “goodhearted Nazi.”

Can You Guard against Your Own Emotions?

Therefore, the danger of overreacting is a major concern when one considers PSA testing; there is a very real possibility of being diagnosed with “cancer” and being swept into the emotion of the moment to undergo unnecessary, radical therapy.  One can’t ignore the fact that 50,000 men seem to fall prey to this trap every year.  The impulse to attack any cancer aggressively can be compelling. People think, “Better than safe than sorry.”  When fear is the primary motivator, it easily overwhelms logic.

We Need Alternatives

So the $64,000 question is, “What can be done to stop so many men from getting unnecessary treatment for the harmless variety of prostate cancer?”  Clearly this is a big issue that needs resolution.  Standard treatment with surgery causes impotence and incontinence and should only be used when absolutely necessary.  Realistically speaking, all types of prostate cancer treatment are detrimental to a man’s quality of life.  Certainly, it’s outlandish to suffer such terrible side effects if the “disease” that is being treated represents no threat to survival.

Shoot the Messenger

In 2011, the government convened an expert panel to study the problem.  After careful review, they recommended the cessation of PSA testing altogether.  Some doctors have taken this recommendation seriously and about 20% of doctors have stopped recommending PSA screening.  However, such a simplistic solution is truly shortsighted considering harmful cancers can only be cured if they are detected and treated at an early stage.  And it seems the real issue doesn’t lie with PSA alone.  The biggest culprit here is the 12-core random needle biopsy.  What we desperately need is an effective alternative to performing a 12-core random needle biopsy in every men with a high PSA.

Find a More Accurate Messenger

Presently, when a primary care physician encounters a patient with a high PSA, he refers him to a urologist who performs a random biopsy.  For many years, random biopsy was the only way to detect harmful prostate cancer at a curable stage.  But these days, men have better options.  One of them is a blood test called 4Kscore.  Another is a urine test called ExoDx.  These assays test multiple biomarkers and provide an estimate of a man’s risk of harboring harmful prostate cancer.  If the results indicate that the risk of a harmful prostate cancer is very low, further testing, particularly the random biopsy, can be avoided.  But what should be done of the 4Kscore or ExoDx indicate that there is the possibility of a dangerous prostate cancer?  Should all of these men undergo a random biopsy?

So Many Problems with Random Biopsy

While the random biopsy can sometimes alert doctors to a dangerous cancer, it has its drawbacks.  First, it over-diagnoses harmless cancer at a furious rate.  For example, even with a relatively normal PSA, say between three and four, a random biopsy diagnoses harmless cancer in one fourth of the men! Second, any cancer diagnosis, even a “harmless” cancer, is emotionally devastating.  Studies show that during the first week after diagnosis the rate of suicides and heart attacks jumps dramatically.  Third, infections from the needles passing through the rectum can lead to hospitalization and even, rarely, to deaths.  Fourth, there is the risk of erectile dysfunction.  Lastly, the random biopsy is rather inaccurate. It misses harmful cancer about 25% of the time.

Imaging Is the Solution

While mammography for breast cancer and CT scans for lung cancer have existed for decades, imaging that consistently differentiates harmless from harmful cancer is very recent.  Historically, prostate imaging with CT, ultrasound or MRI were too inaccurate for diagnosing prostate cancer.  However, after a number of false starts, advances have finally brought multiparametric MRI (MP-MRI) into the winner’s circle.

New Technology Brings Growing Pains

You might assume that new advances immediately revolutionize management.  Not at all.  Many physicians remain totally unaware of MP-MRI, or their unawareness is only partial.  And even if they ordered the test, most haven’t learned yet how to interpret the report or discern if further action is necessary.  Therefore, even well-informed doctors hesitate to abandon the tried-and-true 12-core random biopsy because they are still unfamiliar with the strengths and weaknesses of this new technology.

Scanning at a Center of Excellence

For example, one foundational axiom is to only work with qualified imaging centers for MP-MRI.  There are three components required to achieve reliable results:  A state-of-the-art three-Tesla MRI; technicians who are precisely trained in how to perform prostate imaging; and physicians carefully trained in the interpretation of prostate imaging.  Reading a prostate MRI is not easy.  It takes a doctor around a thousand practice reads to become truly proficient.  Patients should be sure they pursue a center that meets all of these criteria.

How to Read a Scan

Reading a MP-MRI is not particularly difficult once you know the lingo.  If the expert who reads the scan detects an abnormal spot in the prostate (the official term is “lesion”), he assigns it a score of one to five. Men without any lesions, or men who have level one, two or three lesions have a very low chance of harboring harmful cancer.  Assuming that the scan has been performed at a center of excellence, biopsy is not necessary unless there are unusual or extenuating circumstances.

Scan Abnormalities Can Be Targeted

More than half of level 5 lesions and some level 4 lesions can be due to an underlying cancer that is harmful.  In these cases, further evaluation is warranted.  The good news is that the scan provides information about the location of the suspicious lesion inside the prostate.  Thus, it is no longer necessary to rely on blindly stabbing multiple needles throughout the gland.  A trained expert can aim the needle biopsy directly at the lesion.  Studies show that in patients harboring the harmful type of prostate cancer, a targeted biopsy is much more likely to lead to an accurate diagnosis.  Similarly, targeted biopsies are much less likely to lead to an unnecessary diagnosis of a harmless cancer.  So, with MP-MRI the ability to discern harmful from harmless cancers is greatly enhanced.

PSA Screening SaveS Lives

Prostate cancer is a silent disease that, prior to PSA testing, was usually diagnosed after it spread outside the prostate.  Forgoing PSA screening is both foolish and dangerous.  Men should consider getting a baseline PSA at age 40.  Then, to determine how frequently they will test their PSA in the future, men should consider that initial PSA reading, their family history, and if they are of African American descent.  A PSA higher than 2.5 or an abnormal digital rectal exam should trigger further testing with a 4Kscore or ExoDx.  If the results of these tests are not reassuring, a MP-MRI at a center of excellence should be done.

It’s unfortunate that PSA is being unfairly blamed for all the unnecessary prostate cancer treatment when the real culprit is the 12-core random biopsy.  Random biopsy leads to the over-diagnosis of harmless prostate cancer and results in 50,000 men getting unnecessary surgery and radiation every year.  The lack of awareness around this truth is dangerous, and every effort must be made to raise awareness among patients and doctors so that more modern solutions can be substituted for the random 12-core biopsy.