PSA Test: What a Raised Result Means Before You Agree to a Biopsy

A man of fifty-three goes through an executive screening (seker menahalim). Everything comes back normal except one line: a PSA test result of 4.8, flagged with an asterisk beside the laboratory's upper limit. Within three days he is sitting across from a urologist, the word biopsy has been said out loud, and he is convinced he has cancer. In most cases like this, he does not. But the route from that number to a trustworthy answer runs through several steps that almost nobody explains at the first appointment — and those steps are the difference between a considered decision and an unnecessary procedure.

So let us start with the most important sentence here, which is also the one least often said aloud: the number you were given does not say “cancer” and does not say “no cancer”. It says something about your prostate. What exactly depends on your age, on the size of the gland, on what you did in the two days before the blood draw, and above all on what happens next.

The PSA test measures the prostate, not cancer

PSA is a protein made by prostate cells — all of them, not only malignant ones. Its physiological job is to thin seminal fluid, and most of it leaves the body. A small fraction leaks into the bloodstream, and how much leaks depends on two things: how much prostate tissue there is, and how leaky that tissue happens to be at the moment. Cancer does increase the leak, which is why the test is useful at all. But so does a large benign prostate, so does inflammation, and so does mechanical irritation. That is why a raised value is a finding to be worked up, not a diagnosis.

The familiar threshold of 4 nanograms per millilitre is not a biological boundary. It is an administrative convention set decades ago to simplify reporting, and the underlying reality is continuous: there are men below it carrying significant disease, and far more men above it who have nothing at all. Reading a single value against a single line is the least informative way to use this test.

What raises the number when there is no malignancy at all

Before anyone proceeds to biopsy, this list is worth going through. It accounts for a large share of the mildly elevated results that reach us:

• Benign prostatic enlargement (BPH). The commonest cause of all. The gland grows in nearly every man over the years, and more tissue makes more PSA.
• Prostatitis or a urinary tract infection. These can push the value up several-fold. It comes back down after treatment, but that takes time.
• Ejaculation in the day or two before the test. A small effect but a real one — and a shame if it lands you exactly on the threshold.
• Prolonged cycling. Here the evidence is genuinely mixed — pooled reviews have not found a consistent rise — but avoiding a long ride in the two days beforehand is still common advice, if only to keep one more variable out of the answer.
• Procedures in the area: urinary catheterisation, cystoscopy and, of course, a previous biopsy.
• Age itself. The average value rises steadily from the fifth decade onward.

And in the other direction, because this changes decisions too: the 5-alpha-reductase inhibitors — finasteride and dutasteride, taken both for benign enlargement and for hair loss — roughly halve the PSA after a few months of treatment. A man taking one of them who receives a “normal” result may have been handed a misleading answer, so telling your doctor you take them matters. Very high body weight also tends to depress the value somewhat.

One value, against one threshold, with no account taken of age, gland volume or what happened in the previous forty-eight hours — that is the least useful thing you can do with this test.

The first result is almost never the one to decide on

Where the elevation is mild, repeating the test is the sensible first move — a few weeks later, with no ejaculation and no cycling in the preceding two days, and after infection has been ruled out. A substantial proportion of mildly raised values come down on their own on the repeat, and a decision made on the first result alone may be a decision made on noise. The necessary caveat: where there is a clear clinical suspicion, where the value is markedly rather than marginally raised, or where the physical examination is abnormal, nobody waits and nobody repeats. The work-up continues.

Beyond repeating it, there are several ways to read the same number better. None is sufficient alone, and together they move a decision far more than any single figure:

MRI before biopsy — the real change of the past decade

Until fairly recently the pathway was linear: raised PSA, then a systematic biopsy taking ten to twelve cores from the gland to a fixed template rather than to a finding. That approach missed some significant lesions while simultaneously turning up tiny ones of no clinical consequence. The accepted order of operations is now different: multiparametric prostate MRI comes before the biopsy, and what it shows determines whether anything is sampled at all, and from where.

Two key studies established the shift. PROMIS compared the accuracy of imaging against an unusually thorough reference biopsy, and PRECISION randomised men between an MRI-first pathway and systematic biopsy. Both pointed the same way: a pathway that starts with MRI finds more significant disease, finds less clinically insignificant disease, and spares a biopsy in a meaningful proportion of the men referred for one, namely those whose imaging is clean. Findings are graded on the PI-RADS scale from 1 to 5, and where there is a suspicious lesion the biopsy is aimed at it, rather than the gland being sampled to a template alone.

This is not a perfect instrument. A normal MRI does not entirely exclude disease, the quality of the reading depends heavily on the radiologist's experience and on the scanner, and a PI-RADS 3 result is precisely the kind of ambiguous answer that hands the decision back to judgement. Even so, a man referred for biopsy before any imaging has been done is entitled to ask why. In Israel, approval for prostate MRI before biopsy varies between the health funds (kupot holim) and by indication, so it is worth checking in advance with your fund and your urologist. Note also that this is a focused study of one organ, entirely different from the whole-body MRI performed as a screening test.

The real fear is not the diagnosis — it is the treatment

When a man is frightened by a raised PSA, he is almost never frightened of the word. He is frightened of what follows it: surgery or radiotherapy, and with them the risk of losing urinary control and sexual function. That fear is entirely reasonable, and it is also why the concept of active surveillance deserves to be understood.

A large share of the prostate cancers found today are low grade and grow very slowly, and many of them will not harm a man diagnosed in his sixties within his lifetime. In those situations the accepted approach is not immediate treatment but structured follow-up: repeat PSA, physical examination, imaging and repeat biopsy as required — moving to treatment if and when there is evidence of progression. The British ProtecT trial randomised men with localised prostate cancer, most of it picked up by PSA testing, between surgery, radiotherapy and monitoring. After a median of about fifteen years, prostate cancer mortality was low in all three arms — on the order of three per cent — with no significant difference between them. Two fair caveats: the monitoring arm had more local progression and roughly twice the rate of metastatic disease, so surveillance is not free — it trades one risk for another; and the monitoring in that trial was driven mainly by PSA, less intensive than today's protocols with MRI and repeat biopsy.

The controversy, unvarnished

There is no full consensus on population-level PSA screening, and anyone who presents it otherwise is selling a certainty that does not exist. The two large screening trials reached different answers: the European ERSPC study showed a reduction in prostate cancer mortality among men invited to screening, while the American PLCO trial showed no difference — although many men in its control arm were tested anyway, which makes that result hard to interpret.

The strongest argument against testing reflexively is not measurement error but overdiagnosis: finding a cancer that is real under the microscope but would never have caused symptoms or shortened life, where the diagnosis alone brings anxiety, surveillance, and sometimes treatment with all of its side effects. This is not a theoretical problem, and it is why modern guidelines speak of a shared decision rather than blanket screening. Israel has no organised national screening programme for prostate cancer, as it does for breast and colorectal cancer; the test is usually done at the patient's own initiative or the family doctor's, inside an executive screening or by asking at the health fund. The practical meaning: the decision whether to be tested is yours, and it is worth making with your eyes open rather than finding it has arrived as one line inside a panel. The same logic applies to early detection of cancer generally.

Who should start earlier, and when to stop

The usual age to begin discussing the test is around fifty, but three circumstances move that to forty or forty-five: a first-degree relative with prostate cancer, particularly if diagnosed young; African ancestry; and carriage of a BRCA2 variant (and, to a lesser extent, BRCA1). That last point carries particular weight in Israel, because the three founder mutations are notably more common in Ashkenazi Jews — on the order of one carrier in forty. In BRCA2 carriers the risk is both higher and more inclined toward aggressive disease, so this is one setting where structured early surveillance genuinely is justified. If there is breast, ovarian or pancreatic cancer in your family, that is good reason to raise the genetic question with your doctor.

There is a far less discussed other end. As remaining life expectancy shortens — with age, or because of other illness — the benefit of testing falls away, because a slow cancer will not have time to do harm while the work-up that follows it certainly can. Guidelines in Israel and elsewhere do not recommend PSA as routine screening in older men, and the practical question is not the number on your birth certificate but how many good years are plausibly ahead. That too is a conversation rather than a rule.

What to do tomorrow morning with a mildly raised PSA test

• Do not decide on a single value. Ask for a repeat in a few weeks, with no ejaculation and no cycling in the two days before it, and after infection has been excluded.
• Bring the history. PSA values from previous years — from your health fund record or an old executive screening — change the interpretation more than any additional test. A trend says more than a point.
• Declare your medications. Finasteride or dutasteride, even when taken for hair, materially change the number.
• Ask about MRI before biopsy, and what your PSA density is relative to gland volume.
• Ask in advance what happens if low-grade cancer is found. If the answer does not include the option of active surveillance, a second opinion is worth having.

The PSA test is a good tool that is not always used well. The question is not whether the number crossed a line in a laboratory, but what it says about this prostate, at this age, over this stretch of time — and who is looking at all of that together before recommending a procedure. That is part of what we do in a comprehensive assessment, and the same reasoning can be asked of any serious physician. If you have arrived here holding a number with nobody to go through it with you, you can arrange a conversation.