Prostate Specific Antigen (PSA) Test – Why It’s Conducted, Outcomes & More
Posted Dec 16 2010 4:49am
Particular cells in the prostate gland produce a matter known as prostate specific antigen. Abbreviated as PSA, it is a protein & constituent of seminal fluid which keeps it runny in consistency. Majority of the PSA which the prostate gland produces charts its course outside the body via seminal fluid, however miniscule levels of it tend to escape into the blood.
Testing of prostate specific antigen in the blood is done using sophisticated monoclonal antibody method which has high sensitivity in detecting diminutive levels of PSA levels in the blood.
The PSA could subsist on its own (free PSA) or could coalesce along with some substance in the blood (complexed or bound PSA). A summation of these duo types is called total PSA whose measurement is done in the standard PSA test.
The commonest value employed as the max regular level is four nanograms/ml, but as there is an increase in size of the prostate gland & greater production of the PSA protein related to aging hence it is regular to have lesser levels among younger males & high amounts among elder males.
Age-particular PSA levels are:
Age forty to forty-nine years – Upper-normal level 2.5
Age fifty to fifty-nine years – Upper-normal level 3.5
Age sixty to sixty-nine years – Upper-normal level 4.5
Age seventy to seventy-nine years – Upper-normal 6.5
The deployment of such ranges to detect prostate cancer is divisive and there is still no common agreement from the trials conducted that this is superior in comparison to basically employing four nanograms/ mL level as the maximum normal value.
Prostate Cancer Detection Using Prostate Specific Antigen Test
The PSA test is deployed in duo conspicuously diverse manner in regards to prostate cancer detection. It could be employed for males not identified with prostate cancer (to screen or diagnose) & for males who has been identified with the condition (tumor markers or checking test).
As a test to screen or diagnose, any irregular outcome would generally need further tests and anything over four nanogram/ mL though less than ten nanogram/ mL are dubious. But, majority of the males having such extent of irregularity would in fact not be having the disease. When levels cross ten nanogram/ mL, the likelihood augments drastically.
When the PSA test is deployed as a tumor marker or to monitor, then an irregular outcome is indicative of the disease having recurred subsequent to preliminary treatment. For instance, in case surgical excision of the prostate gland has been done via prostatectomy & entire malignancy is present inside the gland then the prostate specific antigen would plummet to 0. In case on consequent testing, outcome of PSA test comes out to be affirmative & reveals rising levels then total cancerous removal was unsuccessful & disease has metastasized.
Irregular PSA level – What are the other causes?
Some conditions could be causal to a high PSA & affecting the prostate gland. BPH (benign prostatic hypertrophy) is a highly pervasive issue wherein aging-related prostate gland expansion occurs. In prostatitis, the prostate gland gets infected thus leading to an irregular rise in PSA. Some situations that also cause irregular PSA level are pitiable blood flow to the prostate gland, prostate biopsies or draining tube from the urinary bladder
Free PSA Test
Largely the PSA that is emitted into blood would attach to proteins and those that don’t are called free PSA who measurement could be done. The amount of this free PSA is lesser among males having prostate cancer than in men having benignant conditions. The precise amount is dependent on what test the lab deploys, however usually below ten percent of free PSA is indicative of cancerous presence. Such a test is highly beneficial when the regular PSA test is amid four & ten nanograms per mL.
PSA test drawbacks
Some proportions of prostate cancers fail to manufacture discernable augments in blood PSA despite being in the later staging. Several preliminary cancers wouldn’t be producing ample PSA for causing a considerably irregular blood level. Hence, it is vital that one should not be totally relying on blood PSA test.
A beneficial added test is physical exam of the prostate conducted by physician called DRE’s or digital rectal examination wherein insertion of a gloved finger is done inside the rectum for palpating prostate for presence of lump, form, size, soreness & firmness.