While the reliability of PSA (prostate specific antigen) test is still a subject of discussions, it is said to be the reason in increased discovery of prostate cancer even in asymptomatic men. In 2006, the disease is reportedly 30% of reason for tumours as more and more men are diagnosed to have prostate cancer.
PSA is produced by both normal and abnormal tissues. It increases as prostate grows when men age or in the presence of cancer or when there is benign conditions like Benign Prostatic Hypertropy.
Out of 100 men who undergo prostatectomy, there is one death. A few experience malfunctions in the bladder while a big percentage suffer from erectile dysfunctions.
PSA testing is clouded by questions and it has its pros and cons to be considered.
- It can help in early detection of prostate cancer even those without symptoms.
- There is a high success rate for treatments due to early detection.
- Side-effects and risks are minimal compared to those in an advanced stage cancer.
- Early detection could mean unnecessary life-quality-changing treatments to a slow progressing prostate cancer that is not instantly life threatening.
- Results could be erratic such as an abnormal reading in the absence of cancer and normal reading even when cancer is present.
- There are no clinical evidences yet that PSA tests have saved lives or have helped prolonged those tested positive and were monitored.
A man, aged above 75 is likely to die due to prostate cancer while 25% of men with a PSA of 3-4 are with prostate cancer, said the the Baltimore Longitudinal Study of Ageing. A deeper understanding of PSA terminologies is important.
- Single PSA Level – this single PSA test evaluates the progress of a possible prostate cancer.
- Free to Total PSA Ratio (FTTR) – this tells apart the reasons for high PSA (whether due to malignant or non-malignant causes). Plasma proteins are affected by PSA reading due to cancer. A low FTTR may mean cancer is present.
- PSA velocity (PSA-V) – PSA that is below 10 is separated into three groups:
PSA <10 and PSA-V <0.3 ng/mL/yr - Unlikely a significant prostate cancer
PSA<10 and PSA –v>0.75ng/mL/yr - Possible malignancy; for further investigation
PSA<10 and PSA-V>1.0ng/mL/yr - Prostate biopsy recommended
- PSA Doubling Time (PSA-DT) – this happens when the disease has grown beyond the prostate and may happen before or after a surgery.
PSA Test Reference
PSA-DT >1 year - Tumour (if present) is likely to be confined to prostate
PSA-DT <9 months - Suggests metastatic disease
PSA <3 in men aged <75 years - Patient unlikely to die from prostate cancer
PSA 3-4 - 25% may have prostate cancer