Prostate Specific Antigen (PSA) is a protein synthesized and
secreted from prostate gland in male that surrounds the first part of urethra,
below the urinary bladder.
It is elevated in benign conditions of prostate as well as
in cancer of prostate; but, most elevated in metastatic prostate cancer.
PSA is also elevated after a digital rectal examination
(DRE) or prostate biopsy. In conditions like benign enlargement of prostate
(BEP) and inflammation of prostate (Prostatitis) PSA is seen to be elevated.
PSA test is approved by FDA for screening of prostate cancer
since long.
Normal level of PSA is said to be <4ng/ml. But, the
problem is that with a raised value, there may not be a cancer; and with normal
or less than normal value, there can be a cancer.
A raised value, even with cancer may not also require
treatment as many prostate cancers are very slow growing; and the person may
die due to some other cause rather than cancer prostate.
On the contrary, some aggressive prostate cancer may
actually get early treatment detected in PSA screening that can be life saving.
So, there is the chance of over-diagnosis and
over-treatment; and at the same time good treatment for some prostate cancer
patients.
Therefore, there has been a debate whether PSA screening is
at all recommended, in otherwise healthy individuals without a family history
of cancer.
Recently, it has been published online April 16 in British
Medical Journal (BMJ) by a research team led by Andrew Vickers, PhD,
from the Memorial Sloan-Kettering Cancer Center in New York City, in
collaboration with teams at the University of Washington in Seattle and Skåne
University Hospital in Malmö, Sweden; which recommends three PSA tests in
lifetime may be all that required for half of men.
They say, “Given existing data on the risk of death by PSA
concentration at age 60, these results suggest that three lifetime PSA tests
(mid to late 40s, early 50s, and 60) are probably sufficient for at least half
of men”.
According to the recommendation, all men with a reasonable
life expectancy could be invited for PSA screening in their mid to late 40s.
Men with a PSA concentration <1.0 µg/L would be advised to return for
screening in their early 50s and then again at age 60, whereas men with PSA
≥1.0 µg/L would return for more frequent screening, with literature suggesting
repeat tests every two or four years.
At the age of 60, men who still had a PSA level below
1 ug/L would be exempt from further screening.
Given existing data, these 3 PSA tests (mid to late 40s,
early 50s, and 60) "are probably sufficient for at least half of
men," the team concludes.
Combined digital rectal examination and PSA test can improve prostate cancer detection.
Combined digital rectal examination and PSA test can improve prostate cancer detection.
