In men taking these supplements, MRI scans showed that their prostate tumors mostly stayed the same size or even got smaller, and the rising PSA levels weren’t hiding any hidden cancer growth.
Scientific Claim
In men with indolent prostate cancer, MRI scans over 16 weeks showed disease stabilization in 164 of 180 participants and shrinkage in 10, with no evidence that PSA progression masked underlying tumor growth.
Original Statement
“Pre and post MRI was available in 180 men to date. In 10, the disease was reported to shrink, 164 stabilised and 6 worsen with PSA progression at a higher than average rate in all these 6, suggesting no PSA masking effect.”
Evidence Quality Assessment
Claim Status
overstated
Study Design Support
Design cannot support claim
Appropriate Language Strength
association
Can only show association/correlation
Assessment Explanation
The claim 'suggesting no PSA masking effect' is inferential and not directly tested. The study lacks a control group for MRI comparison and does not establish causality or exclude confounding. The language is too definitive.
More Accurate Statement
“In men with indolent prostate cancer receiving a phytochemical-rich supplement with or without probiotics, MRI scans over 16 weeks showed tumor stabilization or shrinkage in most cases, and in the few cases with higher-than-average PSA progression, disease worsening was observed, suggesting a possible association between PSA rise and tumor progression, but not confirming absence of masking.”
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.
Randomized Controlled TrialLevel 1bWhether PSA progression reliably predicts tumor growth in men on supplements compared to placebo.
Whether PSA progression reliably predicts tumor growth in men on supplements compared to placebo.
What This Would Prove
Whether PSA progression reliably predicts tumor growth in men on supplements compared to placebo.
Ideal Study Design
A double-blind RCT of 300 men with indolent PCa, with serial multiparametric MRI and PSA measurements every 4 weeks for 24 months, comparing correlation between PSA velocity and tumor volume change in supplement vs. placebo groups.
Limitation: Cannot prove causality between supplement and tumor behavior, only correlation.
Prospective Cohort StudyLevel 2bLong-term validity of PSA as a biomarker for tumor progression in men using gut-targeted supplements.
Long-term validity of PSA as a biomarker for tumor progression in men using gut-targeted supplements.
What This Would Prove
Long-term validity of PSA as a biomarker for tumor progression in men using gut-targeted supplements.
Ideal Study Design
A prospective cohort of 500 men with indolent PCa on active surveillance, tracked with quarterly PSA and annual MRI for 5 years, analyzing correlation between PSA kinetics and tumor volume change, stratified by supplement use.
Limitation: Cannot control for variation in MRI interpretation or timing.
Case-Control StudyLevel 2bWhether men with discordant PSA/MRI findings (PSA rise without tumor growth) are less common with supplement use.
Whether men with discordant PSA/MRI findings (PSA rise without tumor growth) are less common with supplement use.
What This Would Prove
Whether men with discordant PSA/MRI findings (PSA rise without tumor growth) are less common with supplement use.
Ideal Study Design
A case-control study comparing 50 men with PSA rise but stable MRI (cases) to 50 with concordant PSA/MRI progression (controls), matched for age and baseline PSA, assessing supplement use history.
Limitation: Retrospective design limits ability to establish temporal sequence.
Evidence from Studies
Supporting (1)
This study looked at 180 men with slow-growing prostate cancer and used MRI scans to see if their tumors got worse, stayed the same, or shrank — and found that PSA levels didn’t hide real tumor growth, just like the claim says.