Prostate screening for cancer is controversial. It is an attempt at early diagnosis of prostate cancer by testing a wide section of the male population.
There are two methods of prostate screening – digital rectal examination, where a physician checks the prostate for abnormalities with a lubricated, gloved finger, or the prostate-specific antigen (PSA) blood test, which measures the concentration of this enzyme in the blood.
Raised Prostate-Specific Antigen (PSA) Test
The prostate produces the thick, white fluid that – together with sperm from the testicles – creates semen. Also produced by the prostate, is an enzyme (or special protein) that makes the semen fluid enough to be ejaculated. This is prostate-specific antigen, or PSA.
PSA levels in the blood can rise for various reasons, including prostate cancer, enlargement of the prostate [Read more at Benign Prostatic Hyperplasia (BPH)]; infection in the prostate or catheterization, and PSA levels can also be raised for several days after ejaculation.
However, PSA can also be used as an indicator for disease progression.
If a blood test shows a moderately raised PSA level, it can point to enlargement of the prostate. A considerably raised level may be a sign of prostate cancer, although a definite diagnosis depends on more than a PSA test.
PSA testing for prostate cancer is controversial, and could possibly be harmful to some patients: “it is uncertain whether the benefits associated with PSA testing for prostate cancer screening are worth the harms associated with screening and subsequent unnecessary treatment.” Read more
Other research studies, however, suggest the PSA test has successfully reduced death due to prostate cancer. Canada’s new screening guidelines for prostate cancer recommend ‘that men first be tested when in their 40s in order to establish a “baseline” for future risk’. Read more
At present, the UK National Screening Committee (NSC) does not recommend screening men for prostate cancer. Read more
Testing for raised PSA can be performed on request.
Raised PSA Levels after Cancer
If you have had surgery (prostatectomy) or radiation treatment for cancer, all prostate cells, not just prostate cancer cells should have been killed.
But some cells might have previously spread beyond the treatment areas. PSA is produced by all prostate cells, so if any have survived and begin to multiply, the PSA they produce will show up in a test. If your PSA level is rising, further therapy may be required, but that doesn’t necessarily mean that your situation is grave.
How quickly your PSA rises after prostatectomy or radiotherapy can be important in determining how aggressive your cancer is, and can suggest how aggressively it needs to be treated.
If a PSA rate that after treatment has been consistently very low begins to rise, it could mean that the tumour might be starting to grow again, so continued monitoring is essential.
The PSA test is only one of many ways that your specialist can use to track how your prostate cancer is progressing after treatment.