PSA density needs two numbers you usually already have — the PSA and the prostate volume from the MRI or ultrasound — and it takes ten seconds. Yet it is routinely left out of the letter, and the follow-up plan is set on the PSA alone.
Put it in. A man with PSA 6 and a 70 mL prostate is in a different risk stratum from a man with PSA 6 and a 30 mL prostate, and after a negative MRI that difference is roughly two to threefold in the risk of significant cancer over seven years. Writing the density into the letter is what lets the next clinician, who may not have the volume in front of them, set the interval sensibly.
And say what the follow-up interval is and what would change it. 'Repeat PSA in a year' is not a plan; 'biennial PSA, repeat MRI if density reaches 0.10' is.
- Record prostate volume and calculate PSA density whenever imaging has given you a volume
- Write the density, not just the PSA, into the clinic letter
- State the follow-up interval and the trigger that would change it
- Recalculate rather than reusing an old volume — the prostate grows
- Remember a low density is not a discharge: significant cancers still occurred in that group
Why it matters
The number that stratifies risk after a negative MRI is one nobody has to order and almost nobody records.
Read the rest in the app
You have read your two free briefings this month. The app carries all 27 specialties, every morning, free — and this finding is waiting in it.
Scan to keep reading on your phone. No account needed to start.
Tomorrow morning, before your first patient
One edition a day for urology, written by the desk, every claim tied to its paper. Six minutes.
Get the app — free