Once treatment for prostate cancer is finished, PSA blood tests become the main way of checking that the cancer is under control. Waiting for results can be stressful, so it helps to understand what your PSA should do and what a change might mean.
How often PSA is checked
Follow-up schedules vary, but a typical pattern is:
- every three months for the first year or two
- every six months for the next few years
- once a year after that
Your team will tell you your own schedule. Keep a record of your results so you can see the trend. Try to have your blood taken at the same laboratory where possible, as small differences between laboratories can make results harder to compare.
PSA after surgery
After a robotic prostatectomy, the prostate has been removed, so there should be almost no PSA left in the blood. Within about six weeks, PSA usually falls to an undetectable or very low level, often reported as below 0.1 ng/ml or lower.
A very low, stable PSA is a good sign. Small fluctuations in very low readings are common and not usually a concern.
PSA after radiotherapy
After radiotherapy, the prostate remains in place and still makes some PSA. The level falls slowly, often over 18 months to two years or more, to its lowest point, called the nadir.
Some men have a temporary rise in PSA a year or two after radiotherapy, known as a PSA bounce. This is usually harmless and settles without treatment.
If you had hormone therapy with radiotherapy, PSA may fall quickly at first, then change as testosterone recovers after hormone therapy stops.
PSA after focal therapy
After focal therapy, part of the prostate remains, so PSA usually falls but does not become undetectable. Regular MRI scans are often used alongside PSA. Our guide to focal therapy and HIFU explains this.
What biochemical recurrence means
Biochemical recurrence means PSA has risen after treatment in a way that suggests some prostate cancer cells may still be present. It is called "biochemical" because it is found on a blood test, usually before any symptoms or visible changes on scans.
Common definitions are:
- After surgery: a PSA of 0.2 ng/ml or higher, confirmed on a repeat test.
- After radiotherapy: a rise of 2 ng/ml or more above the lowest level reached.
A rising PSA does not necessarily mean cancer is spreading or that it will shorten life. Many men with biochemical recurrence live for many years, and effective treatment is available.
What happens if PSA rises
Your team will look at:
- how quickly PSA is rising, known as doubling time
- how long after treatment the rise began
- the original grade and stage of the cancer
Scans, such as a PSMA PET scan, may help find where the cancer is. Our article on combining MRI and PSMA PET scans explains how they help.
Treatment options after a rise
Options depend on the first treatment and the scan results:
- After surgery: salvage radiotherapy to the area where the prostate was, sometimes with hormone therapy.
- After radiotherapy or focal therapy: salvage surgery, further focal treatment or hormone therapy, in selected men.
- Monitoring: for slow rises, careful observation may be suitable.
NICE guidance on prostate cancer covers the management of rising PSA.
Coping with PSA anxiety
Many men feel anxious before each test. This is very common. Our article on PSA anxiety and fear of recurrence looks at what helps. Prostate Cancer UK also offers support.
Professor Prokar Dasgupta provides long-term follow-up after prostate cancer treatment at The London Clinic. Please contact the clinic to arrange a review.