I’m optimistically predicting a U.S. revolution in prostate biopsies. In some European countries, it has already begun, but on this side of Atlantic we’re still playing catch-up.
In our country, the PSA blood test has been a two-edged sword. On the one hand, it has undoubtedly saved lives by red-flagging suspiciously high PSA results; therefore, it helped catch many cases of aggressive PCa at a moment in time before it had begun to spread. On the other hand, it has also undoubtedly damaged the lives of men who suffered three outcomes as a result of the red flag:
- They were sent for a blind, systematic, and often inaccurate 12+ needle biopsy,
- Those diagnosed with significant PCa were fortunately sent for immediate prostatectomy or radiation, but unfortunately so were many more who were diagnosed with insignificant PCa (Gleason 3+3) which did not require such aggressive treatment,
- And for all who received aggressive treatment (whether or not they needed it), countless were left with leaking urine or ED, some temporary, others permanent.
Thus, thousands of men with insignificant disease did even not need to be biopsied in the first place. They were the victims of the standard screening pathway, that is, PSA screening followed by the existing standard of care (biopsy + treatment). It’s called overdiagnosis and overtreatment. How can this problem be remedied?
A major change in the screening pathway
The solution comes from the Göteborg-2 screening study conducted in Sweden.[i] This is a large, high-level research project in which over 37,000 men ages 50-60 were invited to undergo a standard PSA screening test. A total of 17,980 men enrolled, comprising a 47% response. Those whose PSA was 3.0 ng/mL or higher then had a 3T MRI of the prostate.
Out of those who had MRI, a third (5994 men) were randomly assigned to have both a conventional 12-needle systematic (but random) biopsy, as well as an MRI-guided targeted biopsy; this was the reference or control arm.
The remaining two-thirds (11986 men) were assigned to have an MRI-targeted biopsy only, directed into the suspicious area shown on their MRI scans; this the experimental arm. In other words, the Göteborg-2 trial was designed to find out which pathway performed better at reducing overdetection and overtreatment of PCa patients. If the experimental arm was more accurate at identifying insignificant PCa before biopsy, eliminating the conventional biopsy would be a major change in screening.
For study purposes, insignificant PCa was defined as Gleason 3+3. Significant PCa was defined as Gleason 3+4 or higher. Note: the current trend in clinical opinion about PCa is that insignificant disease does not require immediate aggressive treatment, so even if it’s visible on MRI, no biopsy is needed.
Study results
In the reference arm, 72 men (1.2%) were diagnosed with clinically insignificant PCa, compared with 66 men (0.6%) in the experimental group. In the reference arm, systematic biopsy alone did not perform particularly well, detecting only 10 participants who had clinically significant PCa.
The study authors concluded, “The avoidance of systematic biopsy in favor of MRI-directed targeted biopsy for screening and early detection in persons with elevated PSA levels reduced the risk of overdiagnosis by half…” with very low risk of delaying detection of intermediate-risk tumors.
I don’t know how much more evidence it will take to reduce, if not completely eliminate, unnecessary biopsies. It is in the best interest of patients to continue annual screening, but the standard pathway after the blood test is not! I genuinely hope that the adoption of MRI after abnormal PSA, not biopsy, comes as soon as possible. Let’s quit doing unnecessary biopsies.
NOTE: This content is solely for purposes of information and does not substitute for diagnostic or medical advice. Talk to your doctor if you are experiencing pelvic pain, or have any other health concerns or questions of a personal medical nature.
References
[i] Hugosson J, Månsson M, Wallström J, Axcrona U et al. Prostate Cancer Screening with PSA and MRI Followed by Targeted Biopsy Only. N Engl J Med. 2022 Dec 8;387(23):2126-2137.