No change in PSA after rdiation - why?

My dad recently finished 7 weeks of radiation, after having his prostate removed.  A Prostascan found a few cells in the fatty tissue under the prostate after it had been removed.  He went for a follow-up PSA last week and it was 0.5, the same level as before the radiation. What could this mean? The doctor wants to re-do the PSA in three months.

[Kevin Pho, MD]

After a radical prostatectomy, the PSA should fall to undetectable levels.  Presence of PSA theoretically means prostate, and possibly diseased, tissue remains.

If radiation therapy alone was done, a low-level PSA can fluctuate after treatement.  

I would discuss this question with your father's urologist.  Repeating the PSA is a reasonable thing to do.

Followup with your personal physician is essential.

This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.

Kevin, M.D.
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