The Beatles. Herman’s Hermits. The Who. Gerry and the Pacemakers. The Rolling Stones. These bands and other vocal artists from the United Kingdom brought a fresh new sound to U.S. dominated rock and roll that significantly influenced the sound of popular music. More notably and unforgettably (some might say unforgivingly), they contributed to the wave of youth-driven counterculture. The phenomenon was dubbed the British invasion.

Now, the approach to detecting prostate cancer (PCa) may come under British influence, In this case a band of researchers and clinicians from University College London. Instead of a basic PSA blood test, recently tested the use of prostate biparametric MRI (bpMRI) plus PSA density (density = PSA per prostate volume, and higher density means more PCa risk) as a way to screen for PCa).

You see, the traditional U.S. screening method using the PSA blood test has generated controversy. We know that suspiciously high results lead to too many knee-jerk biopsies. In turn, conventional TRUS biopsies have an error margin ranging from overdetection of insignificant PCa to missing significant PCa altogether. If the British team is correct, their method would revolutionize the traditional method.

The British team points out, “MRI as a screening tool had not been assessed independently of PSA in a formal screening study.”^[i] To test the potential of multiparametric MRI (mpMRI) screening plus a blood test for PSA density, the team designed a clinical trial called ReIMAGINE. As reported by MedscapeUK, it “… is the first to use MRI scans along with PSA density to assess the need for further investigation.”

Participants volunteered for the study based on a patient letter from their general practitioner doctors inviting them for a prostate health check by means of a hospital screening. All volunteers had no previous history of PCa. Of the 2096 letters, 457 responded, and ultimately 303 completed both screenings, the bpMRI and a blood draw to calculate PSA and PSA density. Currently, the British standard for moving to biopsy is PSA equal to or greater than 3.0 ng/ml for a biopsy. In this study, participants were defined as positive if they had a positive screening MRI or a PSA density of >0.12 ng/mL².

Based on the screening, 48 men (16%) had a positive MRI (2/3 of them had PSA less than 3.0 ng/mL). An additional 16 men (5%) had PSA density high enough to be considered screen-positive.

The next steps were as follows:

Men were deemed screen positive if they had a positive sMRI [screening MRI] or a PSA density of >0.12?ng/mL2.11 Screen negative men were informed of their result, and exited the study. Screen positive men were told of their screening result, and recommended to have a referral for National Health Service (NHS) assessment on an urgent suspected cancer pathway. Biopsies were carried out if indicated after multiparametric MRI within a standard NHS pathway. The biopsies were done according to local practice at one of two London hospitals. A transperineal approach was used, with targeting of the MRI lesion and systematic sampling of the peripheral zones. They were followed up for the outcome of this assessment. They exited the study at this point, but gave permission for data to be collected from their standard of care NHS assessment. Clinically significant cancer was defined as any Gleason pattern 4 or above.^[ii]

During the follow-up NHS assessment, which was not part of the study itself, 29 men (9.6%) were found to have clinically significant PCa, while 3 (1%) had insignificant PCa. Keep in mind that the 2/3 of the 48 men who had a positive MRI but a PSA score less than 3.0 ng/mL would not have been sent for further evaluation based on their PSA alone—so their clinically significant disease would not have been detected at all! The authors conclude:

In traditional PSA triage-based screening, these men would have tested negative and have been reassured. This observation might explain why a single PSA-based screening confers so little impact on prostate cancer-specific and all-cause mortality. … The finding in this report is that 2 in 3 men with a positive screening MRI have a PSA <3 ng/mL is a sobering one because MRI lesions are positively associated with clinically significant cancer.

The revolutionary potential of this study is the use of screening MRI to detect cancers. If it were available (and covered by Medicare or insurance), it would pick up significant PCa before PSA would rise, allowing early detection and effective early focal treatment. Although it looks like the screening costs would rise, the cascade of minimalist interventions based on MRI screening would greatly reduce the expenditure of huge medical dollars on unnecessary biopsies, treating biopsy side effects, expensive radical surgery/radiation strategies, and costly procedural side effects.

In short, transforming today’s PCa detection-diagnosis-treatment pathway is one British invasion that could only be welcome.

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] Moore CM, Frangou E, McCartan N on behalf of the Re-Imagine Study group, et al. Prevalence of MRI lesions in men responding to a GP-led invitation for a prostate health check: a prospective cohort study. BMJ Oncology 2023;2:e000057.
[ii] Ibid.